Question

What should come at the place of question mark ( ? ) in the following number series 509, 68, 429, 140, 365, ? *

1 point


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Answer 1

509, 68, 429, 140, 365, 196

Step-by-step explanation:

Given: 509, 68, 429, 140, 365....

Find: The next number in the series.

Solution:

In order to find the next number in the given series, we have to first ascertain the relationship between consecutive numbers.

Upon analyzing the numbers, we find that the relationship is such that it alternates between addition and subtraction of squares starting from 21, 19, 17, 15, 13 and so on.

So the next number in the series will be:

365 - 13²

= 365 - 169

= 196

Hence solved.