ANSWER : 104

Explanation : . Series follows the pattern 4 x 2 + 2 = 10, 10 x 2 + 3 = 23, 23 x 2 + 4 = 50, 50 x 2 + 5 = 105, 105 x 2 + 6 = 216 and so on. Hence, the number 104 should be replaced by 105.

ANSWER : 188

Explanation : . Series has been written in descending order with a differences of 192, 96, 48, 24, 12, 6 respectively. Hence, the number 188 should be replaced by number 184.

ANSWER : 348

Explanation : . Series follows the pattern from the right end as 8 x 2 + 3 = 19, 19 x 2 + 3 = 41, 41 x 2 + 3 = 85, 85 x 2 + 3 = 173, 173 x 2 + 3 = 349, 349 x 2 + 3 = 701. Hence, the number 348 should be replaced by 349.

ANSWER : 87

Explanation : . Series has been written in descending order with a difference of 144, 100, 64, 36, 16 and 4 i.e. squares of even natural numbers. Hence, the number 87 should be replaced by number 100.

ANSWER : 166

Explanation : . Series moves with a difference of squares of odd natural numbers i.e., 1, 9, 25, 49, 81, 121. Hence, the number 166 should be replaced by number 167.