If x is a positive integer and 15 - 2(2x - 1) < 15, the solution set is :

1. {-2, -1}

2. {1, 2, 3, 4, 5, ……}

3. {0, 1, 2, 3, 4, ……}

4. {1, 2, 3, 4, 5, 6}

The centroid of triangle ABC is G = (6, -3). If A = (-6, -3), B = (x, 6) and C = (9, y), then the values of x and y are :

1. x = 6, y = 15

2. x = 15, y = -12

3. x = 15, y = 6

4. x = -15, y = 6

From a solid cylinder of height h cm and base radius r cm, a conical cavity of the same height and same radius is drilled out.

If the slant height of the conical cavity is l cm, the surface area of the remaining solid is :

1. 2πrh + πrl

2. 2πrh - πr² + πrl

3. 2πrh + πrl + πr²

4. 2πrh - πrl + πr²

If m × $\begin{bmatrix$}[r] 2 \ 3 \end{bmatrix} + n\begin{bmatrix}[r] -1 \ 1 \end{bmatrix} = \begin{bmatrix}[r] 10 \ 5 \end{bmatrix}, then the values of m and n are :

1. m = -3, n = -4

2. m = 3, n = -4

3. m = -3, n = 4

4. m = 3, n = 4