Question

42,21,21,31.5,63,?

find the missing number​

Answer 1

Answer:

The missing number of the series is 157.5.

Step-by-step explanation:

Hey Mate,

Given Series : 42, 21 , 21, 31.5, 63, ___

Logic behind the series : This is the multiplication series. As we notice the decrease in the first number, then its stay on point after its sudden increase. If we take examples from 31.5 to 63, the number is doubled. (Mean ×2)

So, Lets test our logic is correct or not.

#1

42 × 0.5 = 21

#2

21 × 1 = 21

#3

21 × 1.5 = 31.5

#4

31.5 × 2 = 63

#5

63 × 2.5 = 157.5

Logic : ×0.5, ×1, ×1.5, ×2, ×2.5, ×3, ×3.5 .....

So,

The missing number of the series is 157.5.

Answer 2

Answer:

missing number of this series is 157.5

Step-by-step explanation:

In this question

We have been given

42, 21, 21, 31.5, 63, ?

therefore,

$42\times 0.5$ = 21

$21\times 1$ = 21

$21\times 1.5$ = 31.5

$31.5\times 2$ = 63

$63\times 2.5$ = 157.5

Here we find out our missing number is 157.5

hence, series is 42, 21, 21, 31.5, 63, 157.5