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Which number will replace the question mark (?) in the following series?
3, 8, 15, 25, 40, 62, 95, ?

  1. A
    141
  2. B
    114
  3. C
    144
  4. D
    111

Solution & Step-by-step Explanation

Let's find the difference between consecutive terms of the series:
8−3=5

15−8=7

25−15=10

40−25=15

62−40=22

95−62=33

Now, let's look at the differences: 5, 7, 10, 15, 22, 33.
Let's find the double difference (difference of differences):

7−5=2

10−7=3

15−10=5

22−15=7

33−22=11

The double differences are 2, 3, 5, 7, 11, which are consecutive prime numbers!
The next prime number after 11 is 13.
Therefore, the next difference will be:

33+13=46
The next term in the series will be:

95+46=141

Practice this question

Try it yourself before checking the explanation above.

Which number will replace the question mark (?) in the following series?
3, 8, 15, 25, 40, 62, 95, ?
A
141
B
114
C
144
D
111

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