General Ability MCQ — 15 Practice Questions with Answers

Explanation

From 1990-91 to 2000-01, the total increased from 9.18 to 19.95 lakhs. If the same percentage increase applies again, the required 2010-11 total is 19.95 × (19.95/9.18) = 43.355..., which rounds to 43.36 lakhs. Hence option D is correct.

Explanation

The tree grows by 1/8 of its current height each year, so each year the height is multiplied by 9/8. Starting from 64 cm, after two years the height is 64 × 9/8 × 9/8 = 81 cm. Hence option A is correct.

Explanation

Expanding the equation gives kx squared - 2kx + 6 = 0. For equal roots, the discriminant must be zero: (-2k) squared - 4(k)(6) = 0, giving 4k(k - 6) = 0. Since k = 0 would not make a quadratic equation, k = 6, so option B is correct.

Explanation

If there are n rows with 3 fewer children in each next row, the row counts form an arithmetic progression with common difference -3. For 6 rows, the total becomes 6 times the first-row count minus 45; equating this to 630 gives the first row as 112.5, which is impossible. For 3, 4, and 5 rows, the first-row counts are integers, so option D is the number of rows not possible.

Explanation

The total of 25 results is 25 x 18 = 450. The first twelve total 12 x 14 = 168, and the last twelve total 12 x 17 = 204. The thirteenth result is 450 - 168 - 204 = 78, so option A is correct.