Mathematics (Core), 2006, WASSCE/WAEC MAY/JUNE, Exam, Paper 1 | Objectives

Paper Info

Year :

2006

Title :

Mathematics (Core)

Exam :

WASSCE/WAEC MAY/JUNE

Paper 1 | Objectives

11 - 20 of 46 Questions

#	Question	Ans
11.	The ratio of boys to girls in a class is 5:3. Find the probability of selecting at random, a girl from the class A. \(\frac{1}{8}\) B. \(\frac{1}{3}\) C. \(\frac{3}{8}\) D. \(\frac{3}{5}\) Show Content Detailed Solution ratio of boys to girls = 5:3 total = 5 + 3 = 8 Pr(girl) = \(\frac{3}{8}\)	C
12.	\(\begin{array}{c\|c} x & 1 & 4 & p \\ \hline y & 0.5 & 1 & 2.5\end{array}\). The table above satisfies the relation y = k\(\sqrt{x}\), where k is a positive constant. Find the value of K. A. 0.5 B. 1 C. 1.5 D. 2 Show Content Detailed Solution y = k\(\sqrt{x}\) when y = 1, x = 4 k = \(\frac{y}{\sqrt{x}}\) = \(\frac{1}{\sqrt{4}}\) = \(\frac{1}{2}\) = 0.5	A
13.	\(\begin{array}{c\|c} x & 1 & 4 & p \\ \hline y & 0.5 & 1 & 2.5\end{array}\). The table below satisfies the relation y - k\(\sqrt{x}\), where k is a positive constant. Find the value of P, A. 2 B. 4 C. 10 D. 25 Show Content Detailed Solution From y = \(\frac{1}{2} \sqrt{x}\) when y = 2.5 or \(\frac{5}{2}\), x = P \(\frac{5}{2} \times \frac{1}{2} \sqrt{P}\) \(\sqrt{P} = \frac{10}{2} = 5\) P = 5² = 25	D
14.	What must be added to x² - 3x to make it a perfect square? A. \(\frac{9}{4}\) B. \(\frac{9}{2}\) C. 6 D. 9 Show Content Detailed Solution x² - 3x + k(perfect square) k = (-\(\frac{3}{2}\))2 ; k = \(\frac{9}{4}\)	A
15.	Given that (2x - 1)(x + 5) = 2x² - mx - 5, what is the value of m A. 11 B. 5 C. -9 D. -10 Show Content Detailed Solution (2x - 1)(x + 5) = 2x² - mx - 5 2x² + 10x - x - 5 = 2x² + 9x - 5 = 2x² - mx - 5 comparing the co-efficient of x -m = 9 m = -9	C
16.	What is the place value of 9 in the number 3.0492? A. \(\frac{9}{10000}\) B. \(\frac{9}{1000}\) C. \(\frac{9}{100}\) D. \(\frac{9}{10}\) Show Content Detailed Solution Place value of 9 in 3.0492 = 0.009 = \(\frac{9}{1000}\)	B
17.	If the simple interest on a sum of money invested at 3% per annum for 2\(\frac{1}{2}\) years is N123, find the principal. A. N676.50 B. N820 C. N1,640 D. N4,920 Show Content Detailed Solution I = N123; R = 3%' T = 2\(\frac{1}{2}\) yrs; P = \(\frac{100 \times 1}{RT}\) P = \(\frac{100 \times 123}{3 \times 2.5}\) principal(P) = N1640	C
18.	A machine valued at N20,000 depreciates by 10% every year. What will be the value of the machine at the end of two years? A. N16,200 B. N1,4,200 C. 12,000 D. 8000. Show Content Detailed Solution D = P(I - \(\frac{R}{100}\))ⁿ where P = N20,000; R = 10%, n = 2 D = 20,000(I - \(\frac{10}{100}\))² = 20000(0.9)² 20,000 x 0.81 = N16,200	A
19.	If 2x + y = 10, and y \(\neq\) 0, which of the following is not a possible value of x? A. 4 B. 5 C. 8 D. 10 Show Content Detailed Solution The value for which the equation is impossible 2x = 10 (if y = 0) x = 5	B
20.	If x + y = 12 and 3x - y = 20, find the value of 2x - y A. 8 B. 10 C. 12 D. 15 Show Content Detailed Solution x + y = 12 + 3x - y = 20 --------------- 4x = 32 x = 8 x + y = 12; 8 + y = 12; y = 12 - 8 = 4 2x - y = 2(8) - 4; 16 - 4 = 12	C

11.	The ratio of boys to girls in a class is 5:3. Find the probability of selecting at random, a girl from the class A. \(\frac{1}{8}\) B. \(\frac{1}{3}\) C. \(\frac{3}{8}\) D. \(\frac{3}{5}\) Show Content Detailed Solution ratio of boys to girls = 5:3 total = 5 + 3 = 8 Pr(girl) = \(\frac{3}{8}\)	C
12.	\(\begin{array}{c\|c} x & 1 & 4 & p \\ \hline y & 0.5 & 1 & 2.5\end{array}\). The table above satisfies the relation y = k\(\sqrt{x}\), where k is a positive constant. Find the value of K. A. 0.5 B. 1 C. 1.5 D. 2 Show Content Detailed Solution y = k\(\sqrt{x}\) when y = 1, x = 4 k = \(\frac{y}{\sqrt{x}}\) = \(\frac{1}{\sqrt{4}}\) = \(\frac{1}{2}\) = 0.5	A
13.	\(\begin{array}{c\|c} x & 1 & 4 & p \\ \hline y & 0.5 & 1 & 2.5\end{array}\). The table below satisfies the relation y - k\(\sqrt{x}\), where k is a positive constant. Find the value of P, A. 2 B. 4 C. 10 D. 25 Show Content Detailed Solution From y = \(\frac{1}{2} \sqrt{x}\) when y = 2.5 or \(\frac{5}{2}\), x = P \(\frac{5}{2} \times \frac{1}{2} \sqrt{P}\) \(\sqrt{P} = \frac{10}{2} = 5\) P = 5² = 25	D
14.	What must be added to x² - 3x to make it a perfect square? A. \(\frac{9}{4}\) B. \(\frac{9}{2}\) C. 6 D. 9 Show Content Detailed Solution x² - 3x + k(perfect square) k = (-\(\frac{3}{2}\))2 ; k = \(\frac{9}{4}\)	A
15.	Given that (2x - 1)(x + 5) = 2x² - mx - 5, what is the value of m A. 11 B. 5 C. -9 D. -10 Show Content Detailed Solution (2x - 1)(x + 5) = 2x² - mx - 5 2x² + 10x - x - 5 = 2x² + 9x - 5 = 2x² - mx - 5 comparing the co-efficient of x -m = 9 m = -9	C

16.	What is the place value of 9 in the number 3.0492? A. \(\frac{9}{10000}\) B. \(\frac{9}{1000}\) C. \(\frac{9}{100}\) D. \(\frac{9}{10}\) Show Content Detailed Solution Place value of 9 in 3.0492 = 0.009 = \(\frac{9}{1000}\)	B
17.	If the simple interest on a sum of money invested at 3% per annum for 2\(\frac{1}{2}\) years is N123, find the principal. A. N676.50 B. N820 C. N1,640 D. N4,920 Show Content Detailed Solution I = N123; R = 3%' T = 2\(\frac{1}{2}\) yrs; P = \(\frac{100 \times 1}{RT}\) P = \(\frac{100 \times 123}{3 \times 2.5}\) principal(P) = N1640	C
18.	A machine valued at N20,000 depreciates by 10% every year. What will be the value of the machine at the end of two years? A. N16,200 B. N1,4,200 C. 12,000 D. 8000. Show Content Detailed Solution D = P(I - \(\frac{R}{100}\))ⁿ where P = N20,000; R = 10%, n = 2 D = 20,000(I - \(\frac{10}{100}\))² = 20000(0.9)² 20,000 x 0.81 = N16,200	A
19.	If 2x + y = 10, and y \(\neq\) 0, which of the following is not a possible value of x? A. 4 B. 5 C. 8 D. 10 Show Content Detailed Solution The value for which the equation is impossible 2x = 10 (if y = 0) x = 5	B
20.	If x + y = 12 and 3x - y = 20, find the value of 2x - y A. 8 B. 10 C. 12 D. 15 Show Content Detailed Solution x + y = 12 + 3x - y = 20 --------------- 4x = 32 x = 8 x + y = 12; 8 + y = 12; y = 12 - 8 = 4 2x - y = 2(8) - 4; 16 - 4 = 12	C