Question

There is a certain relationship between the numbers on the either side of : :. Select a

number from the options which will replace the ‘?’.

3 : 15 : : 7 : ?

a) 35 b) 61 c) 36 d) 64​

Answer 1

Step-by-step explanation:

35 because,

3 × 1 : 3 × 5 = 3:15

7 × 1 : 7 × 5 = 7:35

Answer) Hence, the required number is 35.

Answer 2

Given - Proportion

Find - Missing value

Solution - Representing the given ratio and proportion in fraction form -

$\frac{3}{15} = \frac{7}{x}$

Performing cross multiplication

3*x = 7*15

Shifting 3 from Left Hand Side to Right Hand Side

x = 7*15/3

Performing division followed by multiplication

x = 7*5

x = 35

Hence, the missing value is a) 35.