Question

120,80,40,45,?,5 find the missing no.

Answer 1

Given, 120 , 80 , 40 , 45 , ? , 5

this series is the combination of two different series .e.g., 120, 80 , 40 and 45, ? , 5

here in 120, 80, 40 are in AP where common difference is -40

similarly we have to make 45 , ? , 5 in AP

now if we take 25 in place of ?

we get, 45 , 25 , 5

hence, correct answer should be 25