NOTE MATH FORM 3 - 14 ratio rate

Friday, April 14, 2023

AIRIL BIN AHMAD

RATIO RATE & PROPORTION

BY AIRIL BIN AHMAD


AIRIL BIN AHMAD

RATE

A RATE EXPRESS A RELATIONSHIP INVOLVING 2 QUANTITIES OF DIFFERENT

KINDS.


AIRIL BIN AHMAD

EXAMPLE 1

A typist types 1200 words in one hour. What is her rate of

typing in words per minute?

The rate = 1200 / 60 minute

= 20 words per minute


AIRIL BIN AHMAD

Exercise

1. Alvin paid RM 240 for a year’s road tax for his van. What rate per month was charged?

2. Rohani types 900 words in one hour. What was her rate of typing in words per minute?

3. Maslan paid RM 8460 as quit rent for his house for a year. What rate per month was charged?

4. A man paid RM2400 rent for 4 months. What was the rental rate per month?

5. RM 15.64 is charged for 68 units of electricity. What is the rate in cent per unit?


AIRIL BIN AHMAD

Example 2

If a gram of banana costs 0.14 cent, find the cost of 1kg in ringgit

1 gram = 0.14 cent

1kg or 1000gram = 0.14 x 1000

= 140 cent

= RM 1.40


AIRIL BIN AHMAD

Exercise

1. If a gram of chicken costs 0.5 cent, find the cost of 1kg in ringgit.

2. Sabrina types 50 words in 1 hour. How many words can she type in 3 hour?

3. A car travels 1.5 km in one minute. How far does it travel in 1 hour?

4. If a gram of fish costs 22cent, find the cost of 3kg in ringgit.

5. If a gram of durian costs 0.3 cent, find the costs of 5 kg in ringgit.


AIRIL BIN AHMAD

Example 3

Solutions:

6 metres of silk cloth cost RM72.90

1 metres costs RM72.90 = RM 12.15

6

Therefore 15 metres cost RM12.15 x 15

= RM 182.25

If 6 metres of silk cloth cost RM 72.90, find the cost of 15 metres


AIRIL BIN AHMAD

Exercise

1. If 9 book of the same price cost RM78.75, what is the cost of 24 such books?

2. A bus travels 720 km on 36 litre of petrol. How far can it go on 25 litres of petrol?

3. If 13 litres of petrol costs RM16.25, what is the cost of 18 litres?

4. If 2.5 dozen exercise books costs RM36.00, find the costs of 36 such exercise books?

5. A car traveling at a uniform speed travels a distance of 450 km in 6 hours. How far does it travel in 9 hours?


AIRIL BIN AHMAD

SPEED , DISTANCE & TIME

BY AIRIL BIN AHMAD


AIRIL BIN AHMAD

SPEED , DISTANCE & TIMEFORMULA

D

TS


AIRIL BIN AHMAD

Example 1

Find the speed if:

Distance = 320 km, Time = 5 hours

Speed = 320 km 5 hours

= 64 km per hours


AIRIL BIN AHMAD

Exercise

Find the speed if:

1. Distance = 254 km, Time = 2 hours2. Distance = 218 km, Time = 4 hours3. Distance = 500 km, Time = 6 hours4. Distance = 60 cm, Time = 1.5 sec5. Distance = 500 m, Time = 200 min


AIRIL BIN AHMAD

Example 2

Find the distance if:

Speed = 320 km/h, Time = 5 hours

Distance = 320 km/h X 5 hours = 1600 km


AIRIL BIN AHMAD

ExerciseFind the distance if:

1. Speed = 60 km/h , Time = 5 hours2. Speed = 240 m/s , Time = 4 sec3. Speed = 360 cm/m , Time = 2 min4. Speed = 48 m/s , Time = 4 sec


AIRIL BIN AHMAD

Example 3

Find the time if:

Distance= 6400 km , Speed = 400 km/h

Time = 6400 km/h 400 km/h

= 16 hours


AIRIL BIN AHMAD

Exercise

Find the time if:1.Distance = 60 cm, Speed = 3cm/s2.Distance = 160 km, Speed = 40 km/m3.Distance = 500 m, Speed = 25 m/m4.Distance = 290 km, Speed = 10 km/h5.Distance = 350 cm, Speed = 70 cm/s


AIRIL BIN AHMAD


D

TS


AIRIL BIN AHMAD

AVERAGE SPEED

BY AIRIL BIN AHMAD


AIRIL BIN AHMAD

FORMULA

D

TS

AVERAGE SPEED


AIRIL BIN AHMAD

Example 1

A car travels at an average speed of 75km/h in 20 minutes and 90 km/h in 30 minutes. Calculate the average speed of the car.

A car travels at an average speed of 75km/h in 20 minutes and 90 km/h in 30 minutes. Calculate the average speed of the car.

1 hour/60min =75km1 min = 75 = 1.25

6020 min = 1.25 x 20 = 25 km


AIRIL BIN AHMAD

Example 1

1 hour/60min =90km1 min = 90 = 1.5

6030 min = 1.5 x 30 = 45 km


AIRIL BIN AHMAD

Example 1

Total distance = 25 km + 45 km = 70kmTotal time = 20 min + 30 min= 50min

Average Speed = Distance = 70 kmTime 50 min

= 1.4 x 60 = 84 km/h


AIRIL BIN AHMAD

Exercise

1. A bus travels at an average speed of 90km/h in 30 minutes and 120 km/h in 20 minutes. Calculate the average speed of the bus.


AIRIL BIN AHMAD

Exercise

2. A train travels at an average speed of 80km/h in 15 minutes and 96 km/h in 25 minutes. Calculate the average speed of the train.


AIRIL BIN AHMAD

Exercise

3. A bus travels at an average speed of 100km/h in 30 minutes and 140 km/h in 20 minutes. Calculate the average speed of the bus.


AIRIL BIN AHMAD

Exercise

4. Bakar cycles for 3 hours at an average speed of 18 km/h and then walks for 5 hours at an average speed of 8km/h. Find the average speed for the whole journey.


AIRIL BIN AHMAD

Exercise

5. Khalid took hours to travel 70 km from his house to the Zoo Negara. On his

return journey, he took 30 minutes less. Calculate his average speed (km/h) for the whole journey.

112


AIRIL BIN AHMAD

Exercise6. The diagrams shows the distances

between three taxi stands, P,Q and R.

A taxi traveled from P to Q at an average speed of 60 km/h and from Q to R at 90km/h.Calculate its average speed for the whole journeys.

P Q R140km 60km


AIRIL BIN AHMAD

Exercise6. The diagrams shows the distances

between three taxi stands, P,Q and R.

P Q R140km 60km


AIRIL BIN AHMAD


D

TS


AIRIL BIN AHMAD

ACCELERATION

BY AIRIL BIN AHMAD


AIRIL BIN AHMAD

ACCELERATION

Formula

Acceleration = New speed – Old speed Time


AIRIL BIN AHMAD

Example 1A car accelerates from 75 km/h to 115km/h in 5 seconds to overtake a lorry. Calculate the acceleration in km/h per second.

Solutions:Accelerations= New Speed – Old Speed

Time = 115 km/h – 75km/h

5 seconds = 40km/h = 8 km/h/s

5s


AIRIL BIN AHMAD

Exercise1. A van which is moving at a speed of 45 km/h

accelerates to 75 km/h in 2 minutes. Calculate the acceleration in km/h/m.

2. A car is moving along a road at 12 m/s. It then speeds up to 30 m/s in 5 seconds. What is the car acceleration?

3. A van travels from rest and reaches 60 km/h in 10 minutes. Calculate the acceleration of the car in km/h per minute.


AIRIL BIN AHMAD

DECELERATION

BY AIRIL BIN AHMAD


AIRIL BIN AHMAD

DECELERATION

Formula

Deceleration = New distance – Old Distance Time


AIRIL BIN AHMAD

Example 1The speed of a car changes from 120 km/h to 70km/h in 5 seconds. Calculate the deceleration in km/h per second.

Solutions:Deceleration= New Speed – Old Speed

Time = 70 km/h – 120km/h

5 seconds = -50km/h = -10 km/h/s= 10km/h/s

5s


AIRIL BIN AHMAD

Exercise1. The speed of a bicycle changes from 20m/min to 15 m/min

in 0.4 seconds. Find the deceleration of the bicycle in m/min/sec.

2. Johnny drives his car at a constant speed of 85km/h. Then he slows his speed to 80km/h in 3 seconds. Calculate the deceleration in km/h/s.

Documents

NOTE MATH FORM 3 - 14 ratio rate