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Pinnacle SSC CGL Coaching Centre, Gurudwara Road, Model Town, Hisar, 9729327755 www.ssccglpinnacle.com Page 1
Pinnacle SSC CGL Tier 2 Test Series Paper Code 707 Math
Answer Key
Q ans Q ans Q ans Q ans Q ans
1 d 21 a 41 b 61 b 81 d 2 a 22 a 42 a 62 a 82 a
3 b 23 b 43 c 63 d 83 c 4 b 24 a 44 c 64 a 84 c
5 d 25 a 45 b 65 c 85 c
6 d 26 a 46 b 66 c 86 c 7 c 27 d 47 a 67 a 87 d
8 a 28 b 48 b 68 c 88 c 9 d 29 b 49 b 69 b 89 d
10 b 30 c 50 b 70 c 90 b
11 d 31 a 51 a 71 c 91 a 12 a 32 b 52 d 72 d 92 b
13 b 33 d 53 c 73 a 93 b 14 c 34 a 54 a 74 b 94 c
15 d 35 d 55 c 75 c 95 b 16 b 36 a 56 a 76 a 96 a
17 c 37 b 57 d 77 a 97 d
18 b 38 c 58 c 78 c 98 b 19 c 39 c 59 b 79 c 99 d
20 a 40 c 60 a 80 c 100 a
Explanation:
1. d; Hint: See note.
Let the two-digit no. be 1Ox + y
According to question,
(10x+y)-(10y+x)=54
9x-9y=54; x-y = 6 but we cannot find the number.
2. (a) First find the difference among all and then HCF of the difference
19139 -12288 =6851 ; 28200-19139=9061 ; 28200-12288= 15912
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HCF of 6851 , 9061, 15912 is 221
3. (b) A number is divisible by 18, if it is divisible by 2 and 9 both.
`A number is divisible by 2, if its unit’s digit is an even number.
Unit’s digit of the given number is an even number.
.*. The number to be added must be an even number so that sum of two numbers is even number.
Now, a number is divisible by 9, if sum of its digits is divisible by 9.
Sum of digits of 15762 is 21
If we add 6 then 21+6 =27 is divisible by 7
4. (b) ���
��� =
���
��= 12
5. (d) The least five digit number = 1000
Divide 10000 by 666 we get
Remainder = 10
Hence we add = 666 – 10 = 656
to the least five digit number
Required number = 10656.
6. (d) 10 is substracted
17 – 10 : 24 – 10 = 7 : 14 = 1 : 2
7. (c) Let the sum be Rs. x and the rate be R% p.a.
Then
xR
x4
3
2
25
100
.684
3
4
3
8
R
R
Rate = 6% p.a.
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8. (a); 30��
�= �� 345
20��.��
���= 285
345 + 285 = 630
SP = 630���
���
Per KG SP = ���
��×
���
��� =16.30
9. (d) 30 days
5 M + 7 B ( in 6 days ) can earn = 3825
5 M + 7 B ( in 1 day ) can earn = ����
�
2 M + 3 B ( in 4 days ) can earn = 1050
2 M + 3 B ( in 1 day ) can earn = ����
�
5 M + 7 B = 3825
6
2 M + 3 B = ����
�
THEN 1 M = 75 and 1 B = 37.5
Then 7 M + 6 B = 750
HENCE Rs. 750 Can be earn by ( 7 M + 6 B ) in = 1 day
Hence Rs. 22500 can be earn in = 30 days
10. (b) 2 = 17
13
13
41
1
4
13
11
1
xxx
x = 2 – 17
21
17
13
11. (d) In the second case, 3 pens are substituted by 3 books.
Increase in total cost = Rs. 241 - Rs. 232 = Rs. 9
Difference between cost of one book and one pen — — — Rs. 3
Cost ofI book = Cost of 1 pen + Rs. 3
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Cost of 7 pens + cost of 4 books = Rs. 232
...-. Cost of 11 pens = Rs. 232- 4 x Rs. 3 = Rs. 220
.-. Cost of 1 pen = Rs. 222 = Rs. 20
.'. Cost of 1 book = Rs. 20 + Rs. 3 = Rs. 23
12. (a) Sum of five numbers = 42 × 5 = 210
Sum of eight numbers = 81 × 8 = 648
Average of all numbers = 6613
858
13
648210
13. (b) suppose the number is x.
Acc. the question ,
3��-4x=x+50
3��-5x-50=0
3��-15x+10x-50=0
(3x+5)(x-5)=0
Hense x=5
14. (c) Total weight of 120 students
= (56 × 120) kg = 6720 kg.
Let the number of boys be x.
Then, the number of girls = (120 – x).
60x + (120 – x) × 50 = 6720
60x + 6000 – 50x = 6720
10x = (6720 – 6000) = 720 x = 72.
Number of boys = 72.
Number of girls = (120 – 72) = 48
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15. (d) Ratio of Speeds = 2 : 3 : 4
Ratio of times taken = 3:4:64
1:
3
1:
2
1
16. (b) Sum of the ages of 40 students
= (18 × 40) years = 720 years.
Sum of the ages of 60 students
=
60
2
118 years =
60
2
37years
= 1110 years.
Sum of the ages of 20 new students
= (1110 – 720) years
= 390 years.
Average age of 20 new students
=20
390years =
2
119 years.
17. (c) Let the shares of W, X, Y and Z be Rs. 3x, Rs. 7x, Rs. 9x and Rs. 13x respectively.
W + Y = 11172 Þ (3x + 9x) = 11172
12x = 11172 x = 931.
Required difference = Rs. (13x – 7x) = Rs. 6x
= Rs. (6 × 931) = Rs. 5586
18. (b) Cost price of the table : cost price of chair = : = 3 • 2
Let cost price of a table = Rs. 300
Then cost price of a chair = Rs. 200
Total profit = 3 x 15- 2 ×10 = 45- 20 = Rs. 25
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But actual profit = Rs. 150 =Rs.25 × 6
Cost of a table = 300 × 6 = Rs. 1800
19. (c)
By short cut
200
1SI
CI R
200
1600
618 R
R = 6%
20. (a) B’s income = Average of A & B + Average of B & C - Average of A & C
= Rs. (5500 + 4500 - 4000) = Rs. 6000
21. (A) Rs. 10000
By short cut,
D = P × ��
����
P = �� × ����
�� =Rs. 10000
22. (a) 13 : 14
�� - �� : �� + �� = 27 – 1 : 27 +1 =26 : 28 = 13 : 14
23. (B) 5%
A = P ( 1 + �
��� )�
441 = 400 ( 1 + �
��� )�
���
��� = ( 1 +
�
��� )�
��
�� = ( 1 +
�
��� )
r = 5%
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24. (a) Number of women = (296000 – 166000)
= 130000.
Total number of literates
= .148000100
50296000
Literate men = .116200166000100
70
Literate women = (148000 – 116200) = 31800
25. (a) Rs. 625
Same as que. 21
26 (a) 10% decrease
Let us assume the price is RS.100
Decrease = 25% = Rs. 25
Now the price = Rs. 75
Increase = 20% = 75 × ��
��� = Rs. 15
Now the price = 75 + 15 = Rs. 90
Hence price decrease by 10%
27. (d) Minimum passing marks=120+80=200 = 40%ofthe maximum marks
Maximum marks = 500
28. (b) 11 days
Let us assume the work = 100 units
A B
Time taken (days) 25 20
1 day work (units) 4 5
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1 day work by both A and B = 9 units
5 days work by both = 45 units
Remaining works = 100 – 45 = 55 unit
5 unit is done by B in = 1 day
55 units is done by B in = 11 days
29. (b) If B’s salary is Rs. 100, then A’s salary = Rs. 110% of Rs. 100 = Rs. 110.
But salary of A =Rs. 440 = Rs. 110 × 4
Hence salary of B = Rs. 100 × 4 = Rs. 400
If C’s salary is Rs. 100, then B’s salary = 80% of Rs. 100 = Rs. 80.
But salary of B = Rs. 400 = Rs. 80 × 5
Hence salary of C = Rs. 100 × 5 = Rs. 500
30. (c) Peter completes in 1 day =12
1
piece of work Mohan is 50% more efficient than Peter
Mohan completes in 1 day =8
1
100
150
12
1 piece of work.
Mohan takes 8 days to complete the work.
31. (a) MP =90
10016560= Rs. 18,400
and CP =90
10016560= Rs. 14,400
If no discount is allowed, profit%
= 10014400
1440018400
= %.9
727
32. (b) 3 days
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A can do a work in = 10 days
B can do = 15 days
Hence C will do the work in = �� ��
����� = 6 days
They can do the work together = �� × �� ×�
�� ����� ��� �� =3 days
Or
Let us assume total work = 30 units
A B C
Time taken (days) 10 15 6
1 day work 3 2 5
Hence C will complete the work in 6 days
Now let us assume the total work = 30 units
A B C
Time taken (days) 10 15 6
1 day work (units) 3 2 5
Total work in one days by all = 10 units
Total number of the days taken by them = 3 days
33. (d) 17.25% gain
Total cost price of house for A = Rs. 10000
Selling price for A = 10000 × ���
��� = Rs. 11500
COST price for B = Rs. 11500
Selling price for B RS= 11500 × ��
��� = Rs. 9775
Hence cost price for A = Rs. 9775
Total profit of A = 11000 - 9775 =Rs. 1725
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Profit percentage = ����
����� × 100 = 17.25%
34. (a); 48510 cu cm, 5610 sq cm
Hint: r=7 cm, R = 28 cm and h=45 cm
Capacity =Volume of the frustum
= �
��ℎ(�� + �� + Rr )
= �
�×
��
�× 45 ( 28� + 7� + 28 × 7 ) = 48510 cu cm
Surface area of the bucket = �(� + �)� + �(�� + �� ) = 5610 ���
35. (d) 20%
Total CP= Rs(1200 + 200)= Rs 1400 and SP =Rs 1680
SP> CP, Hence profit and profit % = ���� � ����
���� × 100=20%
36. (a) 3750cub m, 12.5m
Total depth = 15m
If 500 cubic meters of water be drawn off the tank, the level of the water in the tank goes down by 2 meters.
Then capacity of tank = ���
� × 15 = 3750 �� �
Let us assume that breath is b. then lbh = 3750 cu m.
Hence b = ����
�� =
����
���� = 12.5m
37. (b) Part filled by both in 1 min =
20
1
30
1
= .12
1
60
5
60
)32(
Both will fill the tank in 12 minutes
38. (c) RS. 1440
discount = 20 + 10 - �� ��
��� = 28%
total discount = 2000 × ��
��� = Rs. 560
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hence selling price = 2000 – 560 = Rs. 1440
39. (c) Let the slower pipe fill the tank in x minutes.
Then, the faster pipe will fill it in 3
xminutes.
Part filed by both in 1 min
= .431
xxx
But, part filled by both in 1 min. = .36
1
36
14
x x = (36 × 4) = 144.
Hence, the required time is 144 minutes
40. (c) Two equal sides are base and height of the triangle.
.'. Area of the triangle = Base x Height =-�
�x8x8= 32cm2
41. (b) 14% gain
= 100���
���×
��
��� =114 ; so gain of 14%
42. (a) 5:6
Ratio of curved surface area = 5:8 ; Ratio of height = 3:4 ; Ratio of radius = 5:8 \ 3:4 = 5:6
43. (c) 35cm
Ratio between areas of two circles =1:25
Ratio between radii of two circles= 1:5
.'. Radius of second circle=5 x 7 cm = 35 cm
44. (c) Rs900, Rs 1008
Cost price = ��
����� ×100 = Rs. 900
Initial profit = 12%
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Initial selling price = 900 + 900 × ��
��� = Rs. 1008
45. (b) 1% decrease
Rate of change of area = l +b + lb/100
= 10 -10 -�� ��
��� = -1
Hence area will decrease by 1%
46. (b) x = 180 – 40 = 140º
47. (a) -�
�
sum of the roots = ��
�
48. (b) ABC = 90
y + 90 + 50 = 180
y = 40º
49. (b) 204
�� ���� ����
�� = �� +
�
�3 + a +
�
�
=204
50. (b) 40cm
Perimeters of two squares are 24 cm and 32 cm.
Hence sides of two squares are 6cm and 8cm.
Hence areas of two squares are 36��� and 64���.
Hence area of third square is 100���
Hence side of third square is 10cm and perimeter of third square is 40cm.
51. (a) Marked price of the article = 21 × ���
�� = Rs. 30
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52. (d) Ratio of volumes of two cylinders = 2� × 5 ∶ 3� × 4 = 5 : 9
53. (c) 22.86%
CP = Rs. 1404
Profit = Rs. 196
SP = Rs.(1404 + 196 ) =Rs. 1500
if the article is sold at 15% more on selling price
then SP = Rs.( 1500 + 1500 × ��
���) = Rs 1725
hence profit is = Rs. 321
PROFIT % = 22.86%
54. (a) Case I : If 1 = 2, 1 = 2 = 3 = 4
Number of distinct angles is one.
55. c) Rs9375
D = P × ��
���� hence P = D ×
�����
�� = 15 ×
�����
�� = 15 × 625 = Rs. 9375
56. (a) 60° E
C
D
A B
O
Given COA = 36º and DOA =
3
1COA then DOA = 12°
Then ∠��� = 24°
BOC = 180° - COA = 180° – 36° = °
∠��� = �
� × 1 44° = 36°
DOE =∠��� + ∠��� = 24° + 36° = 60°
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57. (d) 2
Roots of the equation x2 – 7x + 10 = 0 are 2 and 5.
Roots of the equation x2 – 10x + 16 = 0 are 2 and 8.
Hence common root is 2.
58. (c) 13.5s
Length of train = 75m
Speed of train = 20 kmph = ��
� mps
Time taken by train to cross a man standing at platform = 75 / ��
� = 13.5s
59. (b) 4
We know that 5� + 12� = 13�
Hence √� = 2 then x = 4
60. (a) 32.5%
M P = Rs. 480
Discount = Rs. 120
S P = Rs. (480 – 120 ) = Rs. 360
Another discount = 10% = Rs. 36
Total discount = Rs. 156 = 32.5%
61. (b) FDG = KCD (corresponding angles)
= ECA (vertically opp. angles)
ECA = 55º
EAC = 40º
E = 180º – (55º + 40º) = 85º
xº = 85º (corresponding angles)
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62. (a) Area of field = 90 x 50= 4500 m2
Area of field dug out = 25 x 20 = 500 m2
.'. Area of remaining field = 4500m2-500 m2=4000m2
Volume of the earth dug out = 25 x 20 x 4 = 2000 m3
2000
Field will rise by = 0.5 metre
63. (d) 1
����65 = ���� 25
����25 + ����25 = 1
64. (a) Let the numbers are x and y.
, Then x +y = 17 and �� - �� = 85
X - y = �2 − �
2
x + y =
��
�� = 5
65. (c) sec2 + cos2 =
2cos2cos
1
=
2
cos
1cos
+ 2 2.
66. (c) rl = × (12)(13) = 156 cm2
67. (a) 1
tan20tan40tan50tan70 = tan20tan40cot 40cot 20 = 1
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68. (c) (1- x6)
(x+ 1) x (1-x) x (x2 – x + 1) x (x2 + x +1) = (x3 + 1) x (1- x3) = (1- x6)
69. (b) a = b
70. (c) The required ratio
=)111111(2).248(
)282448(2
= 7 : 24
71. (c) Relative speed = (72 – 60) km/h = 12 km/h
= 12 × 18
5m/s =
3
10m/s
Total distance covered = (240 + 240) m
= 480 m
Required time =
10
3480 = 144 sec
= 2 min 24 sec
72. (d) 30(√3 + 1 )
A
AB = 60m
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Let us assume that PM = h
∠PBM = 45
�ℎ�� PM = BM = H ℎ���� AM = h + 60
��� ��
�� = tan30
�
���� =
�
√�
h (√3 – 1) =60 h = 30(√3 + 1 )
73. (a) 3
4
if x: y = 7: 3 then putting x = 7 and y = 3 in �����
����� , we find the answer is
�
� .
74. (b) 5 )32( cm
Volume of shell = 4
1× original cylinder
Volume of empty space
= 4
3× original cylinder
r2 × (1000) = 4
3× (10)2 (1000)
r2 = 4
3×100 r = 35 cm
Hence thickness is = 10 - 35 cm = 5 )32( cm
75. (c) 4 km/h
By given condition, 4 =1
6
1
10
xx
x = 4 km/h.
76. (a) 1 : 1 : 1
Given that a + b + c = 4√3 . Here taking a = b = c we get a = b = c = �√�
� then a2 + b2 + c2 = 16.
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Hence a : b : c = 1 : 1 : 1
77. (a) Total distance from temple = 22 )240(x
Where x =3º60tan
hh
So distance =2
2
22
)240(3
h
hbut ,)240(
3
h
=3
1
3
1
)240(3
22
2
h
h
After solving h = 60 6 metre.
78. (c) He covers 10 km in 1 hour (i.e. in 60 minutes)
He will take 6 minutes in covering 1 km.
He rests for 4 minutes after every km.
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Time taken =(6+4)minutes= 10 minutes for every km
Time taken (for first 9 km)= 9 * 10 = 90 minutes
Time taken to cover last one km = 6 minutes
.". Total time taken = 90 + 6 = 96 minutes
Hint: Rest time after 10th km is not added as he has reached his destination.
Alternative Method:
He covers 10 km in 1 hour (i.e. in 60 minutes) and rests for 4 minutes after every km.
He will take rest9 times.
Total time taken = 60 + 9 ×4 = 96 minutes
79. (c) 30°
∠��� = ∠��� = 90°
THEN ∠��� + ∠��� = 180°
LET ∠��� = � �ℎ�� ∠��� = 5�
Hence x + 5x = 180°
X = 30°
80. (c) 10 21 meters
A
B 45 C
Here BC = 10m
∠��� = 45 THEN AB = BC HENCE AB = 10m
Now ��
�� = sin 45 HENCE
��
�� =
�
√� HENCE AC = 10√2m
Hence length of tree = 10 + 10√2 = 10 21 meters
81. (d) Distance covered by the first train in 3 hours = 3 * 80 = 240 km.
Second train gains = 110-80 = 30 km/h
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Second train will meet the first train after ���
�� =8 hours.
Distance covered by the faster train in 8 hours = 8 x 110 = 880 km
82. (a)
10� − 5� = √75 = 5√3
Chord length is double = 10√3
83. (c) -1 +4+3 =6
84. (c)
∠��� = 140°
∠��� = 70 ° ; opposite angle = 180-70 =110°
85. (c) �� + �� + �� + 3��� = (� + � + �)(�� + �� + �� + �� − �� − ��)
A +b +c= �
�+
�
�+
�
� =��
��
86. (c)
87. (d)
88. (c) 15% of the total in 2009 are Engineers which is 60 Total in 2009 = 400 MBA's are 30% US are 15%
Difference = 100
15× 400 = 60
89. (d) In 2010 : Total = 800
maximum difference = 45 – 10 = 35%.
10 5
40°
140° A
B
70° D
c E
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100
35× 400 = 60.
90. (b)
91. (a) Ratio of circum radius and in-radius for equilateral triangle is always 2:1 , so 5cm is in-radius
92. (b) �������� ����� = 180° − 160° = 20° ;��.�� ����� = ���°
�������� �����=
���°
��° =18°
93. (b)
√�
� � = ℎ ;
√�
� × 6 = ℎ ; ℎ =
3√3 ; �������� ���
��� ℎ���ℎ� �� �������� �� √3.������ ������� �ℎ� ℎ���ℎ� ���� 2: 1.
94. (c)
����� ∠��� �� ℎ��� �� 60° �ℎ��ℎ �� ����� = 30° ; ∠��� �� 40° ; ∠��� �� ℎ��� �.�.20° ,∠��� �� 180− 20− 30
= 130°
95. (b) 3� + �
� �= 5 multiply both sides by
�
�
2� + �
�� =
��
� ������ ���ℎ �����
8�� +�
����+ 3 × 2� ×
�
�� (��
�) =
����
��
8�� +�
����=
���
��= 30
��
��
96. (a)
Length of transverse circle = ���� (�����) � = 8 = ���� �
� ; � = √145
97. (d) add 1+1+1 both sides
�
���+ 1 +
�
���+ 1
�
���+ 1 = 1 + 3 = 4
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We get �����
���+
�����
���+
�����
���= 1 + 3 = 4
�
��� +
�
���+
�
���= 4
98. (b) In these triangle ∠� = ∠� , ����� ∠� = ∠� ; �ℎ�� ∠� = ∠� �ℎ��ℎ �� 180− 69− 37 = 74°
99. (d) Suppose ∠� = 90° �ℎ�� �������� ����� ���� �� 90°, ��� ������ ������ 90°�� ��� �� �������� ������ ��
�������� ����� �� 180°. So value will be 0+0+0+ =0 as ��� 90° = 0
100 A.
AD = 27 cm
Centroid divides AD in to 2:1 .
DO will be �
�× 27 =9 ; DN = 12 ; ON=12-9 =3 cm
A
B C
N O
D