Question

Find the missing number.

32, 56, 70
45, 87, 84
115, 180, ?

a) 130
b) 195
c) 295
d) 150​

Answer 1

Correct Question:

Find the missing number.

21, 56, 70

45, 87, 84

115, 180, ?

a) 130

b) 195

c) 295

d) 150

Answer:

a) 130

Step-by-step explanation:

In first row numbers are 21, 56 and 70. Take 21 as A, 56 as B and 70 as C.

Used formula: 2(B - A) = C

Apply this rule on first row,

→ 2(56 - 21) = 70

→ 2(35) = 70

→ 70 = 70

In second row numbers are 45, 87 and 84. Take 45 as A, 87 as B and 84 as C.

→ 2(87 - 45) = 84

→ 2(42) = 84

→ 84 = 84

In their row numbers are 115 and 180. Assume that the missing number is x. Now, take 115 as A, 180 as B and x as C.

→ 2(180 - 115) = x

→ 2(65) = x

→ 130 = x

Hence, the missing number is 130.