Question

Find the wrong number in the given series 891,722,578,457,338,276

Answer 1

In this series the difference between :

891 and 722 = 169

722 and 578 = 144

578 and 457 = 121

From this we get the pattern for the difference as:

13², 12², 11²,........ 1²

The next number from 457 should be:

457 - 10² = 357

And from 357 the next number should be :

357 - 9² = 276

From the working above we discover that the wrong number in the series is 338 since it breaks the pattern.

Answer 2

The wrong number in the given series is 338 (correct, 357).

Step-by-step explanation:

The given series:

891, 722, 578, 457, 338, 276

Find the wrong number = ?

The pattern follow:

$-13^{2} ,-12^{2},-11^{2},-10^{2},-9^{2},....$

722 = 891 - $13^{2}$ = 891 - 169 = 722

587 = 722 - $12^{2}$ = 722 - 144 = 578

457 = 578 - $11^{2}$= 578 - 121 = 457

338 = 457 - $10^{2}$ = 457 - 100 = 357 ≠ 338

276 = 357 - $9^{2}$ = 357 - 81 = 276

Hence, the wrong number in the given series is 338 (correct, 357).