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35 tough questions on remainder
Q1. The unit digit of 23 4 x 34 5 x 45 6 x 67 8 x 78 9 is
A1: Unit digits of respective numbers is 4*3*6*6*7 will have unit digit 4.
Answer is 4.
Q2. If 2 n can exactly divide p! then the value of n which is not possible :a. 43 b. 44 c. 45 d. None of these
A2: We don’t know what’s p!.
Answer is 4.
Find the reminders when
Q3. 6 6 6 . . . . . . Infinity is divided by 10.
A3: Answer is 6
Q4. 888222888222. . . . . up to 9235 digits divided by 53
Q5. 1 x 2 + 3 x 4 + 5 x 6 + 7 x 8 + . . . 10 terms divided by 19
Q6. 11 3 + 9 3 is divided by 7 3
A6: Please share shortcut method; however easy calculation, so would have attempted it.
Q7. 4 4 n + 3 is divided by 7a. 0 b. 1 c. 5 d. None of these
A7: n=1 gives answer 5.
N=2 gives answer 0.
I am assuming ((44^n)+3). Did I interpret something wrong?
Q8. 3 0 + 3 1 + 3 2 + . . . . .201 terms is divided by 13a. 0 b. 12 c. 3 d. None of these
A8: 0, option a.
1+3+9 form a group.
Q9. 1 3 + 2 3 + 3 3 + 1000 3 is divide by 13
A9: Answer is 0.
1000^2 * 1001^2/4 and 1001 is divisible by 13.
Q10. 10 2 + 11 2 + 12 2 + . . . . 28 2 is divided by 19
A10: Answer is 0.
29*57/2 – 10*19/2
Q11. 21 12 – 12 21 is divided by 7
A11: Answer is 1. Check for (3*4) 21
Q12. 23 32 – 9 is divided by 16
A12: 8
232 = 529
529 mod 16 = 1
Q13. 1 3 + 2 3 + 3 3 + 4 3 +. . 10 terms is divided by 1 2 + 2 2 + 3 2 + 4 2 + . . .10 terms
A13: Answer is 4.
100*121*2 / 4*11*21
Q14. 3 37 + 4 37 is divided by 7
A14: Answer is 0
(3+4) mod 7 = (27+64) mod 7 = (243+1024) mod 7
And so on.
Q15. 10 3 + 9 3 is divided by 12 3?
A15: Please share shortcut method; however easy calculation, so would have attempted it.
Q16. 10 11 12 is divided by 13
A16: Answer is 1.
10^2 gives -4 => 10^8 is -1
Q17. 999 9 is divided by 99 9
Q18. 999 9 is divided by 99 9 an then by 9 9
Q19. 12121212. . . 300 times is divided by 99
Q20. 12233344455555…100 terms divided by 7
Q21. (10 3 + 9 3)752 is divided 12 12
Q22. 44444 + 3333 is divided by 7
A22: Answer is 1.
Finding individual reminders. (3 ^ 330) will give reminder 1.
Q23. 1! + 2! + 3! + . . . .70! divided by 100
A23: 1! to 6! Divided by 100;
1+2+6+24+20+20 = 73
Q24. 3456 is divided by 108?
Q25. 1 1 + 2 2 + 3 3 + . . . .100 100 is divided by 4?
A25: 0.
Calculate initial ones, you will see pattern.
Q26. 3 3 3 3 3 3 3 3 3. . .1001 digits. . . . divided by 1001
Q27. 4 + 44 + 444 +. . .100 terms. . divided by 7
Q28. 4 44 is divided by 15.
A28: Answer is 1.
(16 mod 15) is 1.
Q29. 37! 37! Divided by 100
Q30. 17 x 18 x 19 x . . . . 37 divided by 100
A30:Answer is 67
{(37*38/2) – (16*17/2)}/100
Q31. 4 101 is divided by 5
A31: Answer is 4.
4 and 1 is pattern.
Q32. 1 3 + 2 3 + 3 3 + . . . . .99 3 is divided by 10
A32: Answer is 0.
99^2 * 100 ^ 2 / 4
Q33. 2222 5555 + 5555 2222 is divided by 7
Q34. Find the sum of all two-digit numbers that give a reminder 4 when they are divided by 5a. 98,270 b. 99,270 c. 1,02, 090
A34: Looks like wrong options. Answer will be
9 * (28 + 17 * 5)
Q35. When 7179 and 9699 are divided by another natural number N, remainder obtained is same. How many values of N will be ending with one or more than zeroes?a. 24 b. 124 c. 46 d. None of these