Quantitative Aptitude - Arithmetic Ability Questions

Friends, we know we will need gain amount to get gain percent, right. So lets get gain first.

Let the cost price of 1 pen is Re 1

Cost of 8 pens = Rs 8

Selling price of 8 pens = 12

Gain = 12 - 8 = 4

Gain% = gaincost×100%  = 48×100% = 50%

3.78 meters =378 cm = 2 × 3 × 3 × 3 × 7

5.25 meters=525 cm = 5 × 5 × 3 × 7

Hence common factors are 3 and 7

Hence LCM = 3 × 7 = 21

Hence largest size of square tiles that can be paved exactly with square tiles is 21 cm.

the next 2 number in series we need to divide the series into 2 different series

First series : 4 , 6, 12, 30 ??

Second Series : 12,18,26, ??

So we need to see for the pattern for those series in order to find the next two number , we can do this by finding the difference or division , multiplication logic whatever may apply :

• Pattern of Series 1 :

6 divide 4 : 1.5

Next number i.e 12 divided by 6=2

Next number i.e 30 divided by 12 =2.5

So series is going in multiples of 1.5, 2, 2.5, 3 , so on

So first series will look like

4 , 6, 12, 30, 30x3 =90

• Pattern of Series 2 : 12,18,26, ??

Its simple Adding numbers with iterative logic (i.e 6, 8, then followed by 10, 12)

Series will be like 12,18,26,36.

For the next two numbers : Series will be like 4, 12, 6, 18, 12, 26, 30, 36, 90

(x * 5) = (0.75 *8)

X=6/5 = 1.20

The given number series follows a pattern that,

9

9 x 0.5 + 0.5 = 5

5 x 1 + 1 = 6

6 x 2 + 2 = 14

14 x 4 + 4 = 60 (not equals to 56)

60 x 8 + 8 = 488.

Hence, the odd one in the given number series is 56.

Compounded Ratio :: When we compound two or more ratio's with each other through product or multiplication, the result is simply a compound ratio.

Thus, the product of two or more ratios; i.e, ab:cd is a ratio compounded of the simple ratios a:c and b:d.

Required compounded ratio = (2/3 x 6/11 x 11/2) = 2/1. 

Here given 

2, 3, 6, 15, ? , 157.5

2 x 1.5 = 3

3 x 2  = 6

6 x 2.5 = 15

15 x 3 = 45

45 x 3.5 = 157.5

Therefore, the missing number is 45

Let B's present age = x years. Then, A's present age = (x + 9) years.
(x + 9) + 10 = 2(x - 10)

 => x + 19 = 2x - 20

 => x =39.