Question

134=84,178=78,190=40,290=???

Answer 1

Given:

134 = 84, 178 = 78, 190 = 40

To find:

290 = ???

Solution:

The series follows the below technique.

134 = 84

134 - 84 = 50  ⇒ 50 × 1 = 50

178 = 78

178 - 78 = 100   ⇒ 50 × 2 = 100

190 = 40

190 - 40 = 150  ⇒ 50 × 3 = 150

As we can see, the successive subtraction results in multiple of 50. Therefore, the next series subtraction result must be

290 = ???

 ⇒ 50 × 4 = 200

290 - x = 200

290 - 200 = 90

∴ 290 = 90 is the missing series.