In the following number series, a wrong number is given. Find out that number. 8, 18, 40, 86, 178, 370, 752.
Answer & explanation
Correct answer: option 2
The following pattern is observed in the given series: Number x 2+ 2, Resulting number x 2 + (2+2), Resulting number x 2 + (2 + 4)...so on.
8×2+2 =18
18×2+4=40
40×2+6=86
86×2+8=180
It should have been 180, but the series shows 178.
180×2+10=370
370×2+12=752
So, 178 is the wrong number.