11 - 20 of 49 Questions
# | Question | Ans |
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11. |
Given that 2x + y = 7 and 3x - 2y = 3, by how much is 7x greater than 10? A. 1 B. 3 C. 7 D. 17 Detailed Solution2x + y = 7...(1)3x - 2y = 3...(2) From (1), y = 7 - 2x for y in (2) 3x - 2(7 - 2x) = 3 3x - 14 + 4x = 3 7x + 3 + 14 = 17 x = \(\frac{17}{7}\) Hence, 7 x \(\frac{17}{7}\) = 17 - 10 = 7 |
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12. |
Simplify; \(\frac{2}{1 - x} - \frac{1}{x}\) A. \(\frac{x + 1}{x(1 - x)}\) B. \(\frac{3x - 1}{ x(1 - x)}\) C. \(\frac{3x + 1}{ x(1 - x)}\) D. \(\frac{x + 1}{ x(1 - x)}\) Detailed Solution\(\frac{2}{1 - x} - \frac{1}{x}\) = \(\frac{2x - 1(1 - x)}{x(1 - x)}\)= \(\frac{2x - 1(1 + x)}{x(1 - x)}\) = \(\frac{3x - 1}{x(1 - x)}\) |
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13. |
Make s the subject of the relation: P = S + \(\frac{sm^2}{nr}\) A. s = \(\frac{mrp}{nr + m^2}\) B. s = \(\frac{nr + m^2}{mrp}\) C. s = \(\frac{nrp}{mr + m^2}\) D. s = \(\frac{nrp}{nr + m^2}\) Detailed SolutionP = S + \(\frac{sm^2}{nr}\)P = S(1 + \(\frac{m^2}{nr}\)) P = S(1 + \(\frac{nr + m^2}{nr}\)) nrp = S(nr + m2) S = \(\frac{nrp}{nr + m^2}\) |
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14. |
Factorize; (2x + 3y)2 - (x - 4y)2 A. (3x - y)(x + 7y) B. (3x + y)(2x - 7y) C. (3x + y)(x - 7y) D. (3x - y)(2x + 7y) Detailed Solution(2x + 3y)2 - (x - 4y)2= (2x + 3y)(2x + 3y) - (x - 4y)(x - 4y) = 4x2 + 12xy + 9y2 - (x2 - 8xy+ 16y2) = 4x2 + 12xy + 19y2 - x2 + 8xy - 16y2 = 3x2 + 20xy - 7y2 = 3x2 + 21xy - xy - 7y2 = 3x(x + 7y) - y(x + 7y) = (3x - y)(x + 7y) |
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15. |
The curve surface area of a cylinder, 5cm high is 110cm 2. Find the radius of its base. [Take \(\pi = \frac{22}{7}\)] A. 2.6cm B. 3.5cm C. 3.6cm D. 7.0cm Detailed SolutionCurved surface area of cylinder = 2\(\pi\)rh110 = 2 x \(\frac{22}{7}\) x r x 5 r = \(\frac{110 \times 7}{44 \times 5}\) = 3.5cm |
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16. |
The volume of a pyramid with height 15cm is 90cm3. If its base is a rectangle with dimension xcm by 6cm, find the value of x A. 3 B. 5 C. 6 D. 8 Detailed SolutionVolume of pyramid = \(\frac{1}{3}\)lbh90 = \(\frac{1}{3} \times x \times 6 \times 15\) x = \(\frac{90 \times 33}{6 \times 15}\) = 3 |
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17. |
A straight line passes through the points P(1,2) and Q(5,8). Calculate the gradient of the line PQ A. \(\frac{3}{5}\) B. \(\frac{2}{3}\) C. \(\frac{3}{2}\) D. \(\frac{5}{3}\) Detailed SolutionLet: (x1, y1) = (1, 2)(x2, y2) = (5, 8) The gradient m of \(\bar{PQ}\) is given by m = \(\frac{y_2 y_1}{x_2 - x_1}\) = \(\frac{8 - 2}{5 - 1}\) = \(\frac{6}{4}\) = \(\frac{3}{2}\) |
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18. |
A straight line passes through the point P(1,2) and Q A. \(4\sqrt{11}\) B. \(4\sqrt{10}\) C. \(2\sqrt{17}\) D. \(2\sqrt{13}\) Detailed Solution|PQ| = \(\sqrt{(x_2 - X- 1) + (y_2 - y_1)^2}\)= \(\sqrt{(5 - 1)^2 + (8 - 2)^2}\) = \(\sqrt{4^2 + 6^2}\) = \(\sqrt{16 + 36}\) = \(\sqrt{52}\) = 2\(\sqrt{13}\) |
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19. |
If cos \(\theta\) = x and sin 60o = x + 0.5 0o < \(\theta\) < 90o, find, correct to the nearest degree, the value of \(\theta\) A. 32o B. 40o C. 60o D. 69o Detailed Solutionsin 60o = x + 0.5 0o(given)0.8660 = x + 0.5 0.8660 - 0.5 = x x = 0.3660 cos\(\theta\) = x(given) cos\(\theta\) = 0.3660 Hence, \(\theta\) = cos-1(0.3660) = 68.53o = 69o (nearest degree) |
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20. |
\(\begin{array}{c|c} A. 50 B. 55 C. 60 D. 65 Detailed SolutionNumber of students in the club is10 + 24 + 8 + 5 + 3 = 50 |
11. |
Given that 2x + y = 7 and 3x - 2y = 3, by how much is 7x greater than 10? A. 1 B. 3 C. 7 D. 17 Detailed Solution2x + y = 7...(1)3x - 2y = 3...(2) From (1), y = 7 - 2x for y in (2) 3x - 2(7 - 2x) = 3 3x - 14 + 4x = 3 7x + 3 + 14 = 17 x = \(\frac{17}{7}\) Hence, 7 x \(\frac{17}{7}\) = 17 - 10 = 7 |
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12. |
Simplify; \(\frac{2}{1 - x} - \frac{1}{x}\) A. \(\frac{x + 1}{x(1 - x)}\) B. \(\frac{3x - 1}{ x(1 - x)}\) C. \(\frac{3x + 1}{ x(1 - x)}\) D. \(\frac{x + 1}{ x(1 - x)}\) Detailed Solution\(\frac{2}{1 - x} - \frac{1}{x}\) = \(\frac{2x - 1(1 - x)}{x(1 - x)}\)= \(\frac{2x - 1(1 + x)}{x(1 - x)}\) = \(\frac{3x - 1}{x(1 - x)}\) |
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13. |
Make s the subject of the relation: P = S + \(\frac{sm^2}{nr}\) A. s = \(\frac{mrp}{nr + m^2}\) B. s = \(\frac{nr + m^2}{mrp}\) C. s = \(\frac{nrp}{mr + m^2}\) D. s = \(\frac{nrp}{nr + m^2}\) Detailed SolutionP = S + \(\frac{sm^2}{nr}\)P = S(1 + \(\frac{m^2}{nr}\)) P = S(1 + \(\frac{nr + m^2}{nr}\)) nrp = S(nr + m2) S = \(\frac{nrp}{nr + m^2}\) |
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14. |
Factorize; (2x + 3y)2 - (x - 4y)2 A. (3x - y)(x + 7y) B. (3x + y)(2x - 7y) C. (3x + y)(x - 7y) D. (3x - y)(2x + 7y) Detailed Solution(2x + 3y)2 - (x - 4y)2= (2x + 3y)(2x + 3y) - (x - 4y)(x - 4y) = 4x2 + 12xy + 9y2 - (x2 - 8xy+ 16y2) = 4x2 + 12xy + 19y2 - x2 + 8xy - 16y2 = 3x2 + 20xy - 7y2 = 3x2 + 21xy - xy - 7y2 = 3x(x + 7y) - y(x + 7y) = (3x - y)(x + 7y) |
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15. |
The curve surface area of a cylinder, 5cm high is 110cm 2. Find the radius of its base. [Take \(\pi = \frac{22}{7}\)] A. 2.6cm B. 3.5cm C. 3.6cm D. 7.0cm Detailed SolutionCurved surface area of cylinder = 2\(\pi\)rh110 = 2 x \(\frac{22}{7}\) x r x 5 r = \(\frac{110 \times 7}{44 \times 5}\) = 3.5cm |
16. |
The volume of a pyramid with height 15cm is 90cm3. If its base is a rectangle with dimension xcm by 6cm, find the value of x A. 3 B. 5 C. 6 D. 8 Detailed SolutionVolume of pyramid = \(\frac{1}{3}\)lbh90 = \(\frac{1}{3} \times x \times 6 \times 15\) x = \(\frac{90 \times 33}{6 \times 15}\) = 3 |
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17. |
A straight line passes through the points P(1,2) and Q(5,8). Calculate the gradient of the line PQ A. \(\frac{3}{5}\) B. \(\frac{2}{3}\) C. \(\frac{3}{2}\) D. \(\frac{5}{3}\) Detailed SolutionLet: (x1, y1) = (1, 2)(x2, y2) = (5, 8) The gradient m of \(\bar{PQ}\) is given by m = \(\frac{y_2 y_1}{x_2 - x_1}\) = \(\frac{8 - 2}{5 - 1}\) = \(\frac{6}{4}\) = \(\frac{3}{2}\) |
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18. |
A straight line passes through the point P(1,2) and Q A. \(4\sqrt{11}\) B. \(4\sqrt{10}\) C. \(2\sqrt{17}\) D. \(2\sqrt{13}\) Detailed Solution|PQ| = \(\sqrt{(x_2 - X- 1) + (y_2 - y_1)^2}\)= \(\sqrt{(5 - 1)^2 + (8 - 2)^2}\) = \(\sqrt{4^2 + 6^2}\) = \(\sqrt{16 + 36}\) = \(\sqrt{52}\) = 2\(\sqrt{13}\) |
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19. |
If cos \(\theta\) = x and sin 60o = x + 0.5 0o < \(\theta\) < 90o, find, correct to the nearest degree, the value of \(\theta\) A. 32o B. 40o C. 60o D. 69o Detailed Solutionsin 60o = x + 0.5 0o(given)0.8660 = x + 0.5 0.8660 - 0.5 = x x = 0.3660 cos\(\theta\) = x(given) cos\(\theta\) = 0.3660 Hence, \(\theta\) = cos-1(0.3660) = 68.53o = 69o (nearest degree) |
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20. |
\(\begin{array}{c|c} A. 50 B. 55 C. 60 D. 65 Detailed SolutionNumber of students in the club is10 + 24 + 8 + 5 + 3 = 50 |