# Numbers Questions

Q:

 A) 961 x 861 B) 961 x 961 C) 961 x 2 D) 29791

Explanation:

We know that ${a}^{m}×{a}^{n}={a}^{m+n}$

$\therefore {\left(31\right)}^{31-27}$ = ${31}^{4}$ = 961 x 961.

Filed Under: Numbers - Quantitative Aptitude - Arithmetic Ability
Exam Prep: CAT
Job Role: Bank PO

6 2464
Q:

If

 A) 144 B) 72 C) 36 D) 24

Explanation:

a4 = a2 x a2 = 12 x 12 = 144

0 2387
Q:

3x + y = 19  and x + 3y = 1. Find the value of 2x + 2y

 A) 20 B) 18 C) 11 D) 10

Explanation:

To solve a pair of simultaneous equations such as those given we can add or subtract them.

Adding we get 4x + 4y = 20

Therefore 2x + 2y = 10

0 2379
Q:

A straight fence is to be constructed from posts 6 inches wide and separated by lengths of chain 5 feet long. If a certain fence begins and ends with a post, which of the following could be the length of the fence in feet? (12 inches = 1 foot).

 A) 17 B) 18 C) `19 D) 20

Explanation:

The fence will consist of one more post than there are chains. (e.g. P-c-P-c-P).

Therefore, a total length has to be a multiple of the length of the chain plus one post (5.5) plus one post extra.We have length = (5.5n + 0.5), where n can be any positive whole number. If n= 3, length =17

2 2302
Q:

For how many integer values of n will the value of the expression 4n + 7 be an integer greater than 1 and less than 200?

 A) 48 B) 49 C) 50 D) 51

Explanation:

1 < 4n + 7 < 200

n can be 0, or -1

n cannot be -2 or any other negative integer or the expression 4n + 7 will be less than1.

The largest value for n will be an integer < (200 - 7) /4

193/4 = 48.25, hence 48

The number of integers between -1 and 48 inclusive is 50

0 2003
Q:

Find the next number in the series 125, 80, 45, 20, ....

 A) 5 B) 15 C) -5 D) 10

Explanation:

The pattern is -45, -35, -25, -15

The next number = 20-15= 5

10 1961
Q:

Find the next number in the series 14, 916, 2536,......

 A) 4981 B) 6481 C) 4964 D) 6449

Explanation:

The pattern is

$\therefore$The next number= = 4964

11 1872
Q:

Find the unit digit of 4198 + 612345 + 34866 + 2411 + 1.

 A) 3 B) 2 C) 1 D) 0

Explanation:

Given that, ${4}^{198}+{6}^{12345}+{348}^{66}+{24}^{11}+1$

Now Power Cycle of

4 is 4, 6

6 is 6

8 is 8, 4, 2, 6

1 is 1

${4}^{198}$- 198 is even number , So the unit digit value is 6

${6}^{12345}$ - It is always 6

${348}^{66}$-  66/4 the remainder is 2 , So the second value is 4

${24}^{11}$- 11 is odd number, So the unit digit value is 4

1 - It is always 1

Total = 21

Therefore, The unit digit is 1