1 $\left(-\frac{6.1}{0.61}\right) \times \frac{0.756}{75.6} =$ flag bookmark A −0.0001 B −0.001 C −0.01 D −0.1 $(-10) \times 0.01 = -0.1$.
2 The value of $\sqrt{500\,000}$ is between flag bookmark A 60 and 70 B 70 and 80 C 600 and 700 D 700 and 800 $\sqrt{500\,000} = 707.1$, which is between 700 and 800 ($700^2 = 490\,000$, $800^2 = 640\,000$).
3 The speed of a motorcycle decreases from 60.5 km/h to 40.8 km/h in 5 minutes. Find the decrease in speed per minute. flag bookmark A 3.24 km/h B 3.64 km/h C 3.94 km/h D 3.98 km/h Decrease = 60.5 − 40.8 = 19.7 km/h. Per minute: 19.7 ÷ 5 = 3.94 km/h.
4 In Diagram 1, AB, CD and PQ are straight lines that intersect at point O. Calculate the conjugate angle of $x$. flag bookmark A 40° B 50° C 140° D 320° ∠BOQ = 50°, so ∠POA = 50° (vertically opposite), and x = ∠COP = 90° − 50° = 40°. The conjugate angle of x = 360° − 40° = 320°.
5 Given that $a = 2 \times 10^4$, find the value of $16a^3$. Give the answer in standard form. flag bookmark A $1.28 \times 10^{14}$ B $1.28 \times 10^{12}$ C $6.4 \times 10^9$ D $3.2 \times 10^8$ $16(2 \times 10^4)^3 = 16 \times 8 \times 10^{12} = 128 \times 10^{12} = 1.28 \times 10^{14}$.
6 Convert the straight line equation $x - 2y = 4$ to the form $\frac{x}{a} + \frac{y}{b} = 1$. flag bookmark A $\frac{x}{2} + \frac{y}{4} = 1$ B $\frac{x}{4} + \frac{y}{2} = 1$ C $\frac{x}{2} + \frac{y}{-4} = 1$ D $\frac{x}{4} + \frac{y}{-2} = 1$ Divide by 4: $\frac{x}{4} - \frac{2y}{4} = 1$, i.e. $\frac{x}{4} + \frac{y}{-2} = 1$.
7 Diagram 2 shows the graph of the function $y = x^2 - 4$. Find the value of $m$. flag bookmark A −1 B −1.5 C −2 D −4 T4 Chapter 1.1g Roots of a Quadratic Equation The x-intercepts are the roots of $x^2 - 4 = 0$: $(x - 2)(x + 2) = 0$, x = 2 or −2. So m = −2.
8 Diagram 3 shows a regular octagon. Find the value of $x$. flag bookmark A 25° B 30° C 35° D 38° Interior angle of a regular octagon = $\frac{(8 - 2) \times 180°}{8} = 135°$. So $3x + 30° = 135°$, $3x = 105°$, x = 35°.
9 A number is chosen at random from the set $\{x : x$ is a positive integer and $x \leq 40\}$. Find the probability of getting a perfect square. flag bookmark A $\frac{3}{20}$ B $\frac{1}{10}$ C $\frac{1}{8}$ D $\frac{1}{50}$ Perfect squares: 1, 4, 9, 16, 25, 36 (6 numbers). P = $\frac{6}{40} = \frac{3}{20}$.
10 The data below shows the hourly wages, in RM, of a group of workers. RM8, RM5, RM15, RM6, RM7, RM6, RM5, RM6, RM5, RM5, RM9, RM7, RM4, RM3, RM4, RM7 Calculate the mean wage after the extreme value is excluded from the data. flag bookmark A RM5.00 B RM5.80 C RM6.00 D RM6.20 The 16 wages add up to RM102. RM15 is far above the rest, so it is the extreme value. Without it: $\frac{102 - 15}{15} = \frac{87}{15} = 5.80$.