6, 18, 3, 21, 7, 56, ?

8, 9, 8, 7, 10, 9, 6, 11, 10, ?, 12

One term in the number series is wrong. Find out the wrong term.<br> 196, 169, 144, 121, 101

Choose the missing terms out of the given alternatives : A, I, P, V, A, E, ?

Choose the missing terms out of the given alternatives : Y, B, T, G, O, ?

2, 3, 5,7,11,?, 17

Choose the missing terms out of the given alternatives.<br> DHL, PTX, BFJ, ?

One term in the number series is wrong. Find out the wrong term.<br> 3, 7, 15, 39, 63, 127, 255, 511

Choose the missing terms out of the given alternatives.<br> Z, ?, T, ?, N, ?, H, ?, B