# Number System

## Trending Questions

**Q.**

The traffic lights at three different road crossings change after every $48$ seconds, $72$ seconds and $108$ seconds respectively. If they change simultaneously at $7\mathrm{a}.\mathrm{m}.$ at what time will they change simultaneously again?

**Q.**

Find the greatest number of 6 digits exactly divisible by $24,15$ and $36$.

**Q.**The sum of n terms of the series 4 + 44 + 444 + ......... is

(4/81) [10n+1−9n−1]

(4/81) [10n−1−9n−1]

(4/81) [10n+1−9n−10]

(4/81) [10n−9n−10]

**Q.**Two numbers, x and y are such that when

divided by 6, they leave remainder 4 and 5

respectively. Find the remainder when x3+y3 is divided by 6?

- 2
- 3
- 4
- 5

**Q.**Given digits 2, 2, 3, 3, 3, 4, 4, 4, 4 how many distinct 4 digit numbers greater than 3000 can be formed ?

- 50
- 51
- 52
- 54

**Q.**Find the number of divisors 1420.

- 14
- 15
- 13
- 12

**Q.**The sum of two numbers is 15 and their geometric mean is 20% lower than their arithmetic mean. Find the numbers.

- 11, 4
- 12, 3
- 13, 2
- 10, 5

**Q.**If A381 is divisible by 11, find the value of the smallest natural number A?

- 5
- 6
- 7
- 9

**Q.**What is the unit digit of

3953×2723×3612

- 2
- 4
- 6
- 8

**Q.**Find the least number which being divided by 9, 12, 16 and 30 leaves in each a remainder 3 ?

- 623
- 723
- 728
- None of these

**Q.**Find the least multiple of 11 which when divided by 8, 9, 12, 14 leaves 4 as remainder in each case.

- 1012
- 1037
- 1090
- None of these

**Q.**The LCM of two number is 12 times their HCF. The sum of HCF and LCM is 403. If one number is 93 find the other.

- 134
- 124
- 128
- None of these

**Q.**What will be the maximum sum of 44, 42, 40, ......?

502

504

506

500

**Q.**The product of three consecutive natural numbers, the first of which is an even number, is always divisible by

- 12
- 24
- 8
- All of these

**Q.**When a four digit number is divided by 85 it leaves a remainder of 39. If the same number is divided by 17 the remainder would be?

- 2
- 5
- 7
- 9

**Q.**Find the pairs of natural numbers whose least common multiple is 78 and the greatest common divisor is 13.

- 58 and 13 or 16 and 29
- 38 and 23 or 36 and 49
- 18 and 73 or 56 and 93
- 78 and 13 or 26 and 39

**Q.**What would be the smallest natural number which when divided either by 20 or by 42 or by 76 leaves a remainder of 7 in each case?

3047

6047

7987

63847

**Q.**Find the greatest number less than 10000 which is divisible by 48, 60 and 64

- 9600
- 8500
- 7600
- None of these

**Q.**N is a natural number, then how many values of N are possible such that 6N3+3N2+N+24N

is also a Natural Number?

- 6
- 7
- 8
- 9

**Q.**A man wrote all the natural numbers starting from 1 in a series. What will be the 50th digit of the number?

- 1
- 2
- 3
- 4

**Q.**What is the tens digit of the sum of the first 50 terms of 1, 11, 111, 1111, 11111, 111111, .........?

- 2
- 4
- 5
- 8

**Q.**The sum of eight consecutive odd numbers is 656. The average of four consecutive even numbers is 87. What is the sum of the smallest odd number and second largest even number?

**Q.**I have to spend 1/10 of my income on house rent, 1/10 of remainder on conveyance 1/3 of further remainder on children's education after which I have Rs. 648 left over. What is my income?

- Rs. 1200
- Rs. 1400
- Rs. 1700
- None of these

**Q.**GCD of x2−4 and x2+x−6 is

- x+2
- x−2
- x2−2
- x2+2

**Q.**The sum of the digits of a two-digit number is 10, while when the digits are reversed, the number decreases by 54. Find the changed number.

- 28
- 19
- 37
- 46

**Q.**How many number of zeros are there if we multiply all the prime numbers between 0 and 200.

- 1
- 2
- 3
- 4

**Q.**The sum of all the natural numbers between 1 and 101 which are divisible by 5 is

1000

1050

1500

2550

**Q.**A man had two sons. To the elder he gave511 of his property, to the younger 511 of remainder, the rest to the widow.

Find the share of the sons if the widow gets RS.3600.

- Rs. 1200, 1000
- Rs. 6000, 2000
- 7500, 1000
- None of these

**Q.**Fill in the blank indicated by a star in the number 4*56 so as to make it divisible by 33

- 3
- 4
- 5
- None of these

**Q.**What is the remainder when N=(1!+2!+3!+...1000)40 is divided by 10?

- 1
- 3
- 7
- 8