[3 marks sum]

Question 13 Marks

If $x = 10$, evaluate:
$6x^2 – 25x$

Answer

$6x^2 – 25x$
$= 6(10)^2 − 25(10)$
$= (6 \times 10 \times 10) − (25 \times 10)$
$= 600 − 250$
$= 350$

Question 23 Marks

If $m =2$, evaluate : $\frac{1}{4} \times m ^3$

Answer

$\frac{1}{4} \times m ^3$
$=\frac{1}{4} \times(2)^3$
$=\frac{1}{4} \times 2 \times 2 \times 2$
$=\frac{1}{4} \times 8$
$=2$

View full question & answer→

Question 33 Marks

If m$ = 2,$ evaluate:
$15m^2 – 10m$

Answer

$15m^2 – 10m$
$= 15 (2)^2 − 10(2)$
$= (15 \times 2 \times 2) − (10 \times 2)$
$= 60 − 20$
$= 40$

View full question & answer→

Question 43 Marks

From the formula $B = 2a^2 – b^2,$ calculate the value of $B$ when $a = 3$ and $b = − 1.$

Answer

$B = 2a^2 – b^2$
Put the values of $a = 3$ and $b = − 1$ in above equation
$B = 2 \times (3)^2 – (− 1)^2$
$B = 18 – 1$
$B = 17$
Value of $B$ is $= 17$

View full question & answer→

Question 53 Marks

If $p = − 10$, evaluate:
$3p^2 – 20p$

Answer

$3p^2 – 20p$
$= (3 \times p \times p) − (20 \times p)$
$= (3 \times (− 10) \times (− 10)) − (20 \times (− 10))$
$= 300 − (− 200)$
$= 300 + 200$
$= 500$

View full question & answer→

Question 63 Marks

If p = − 10, evaluate:
6p + 50

Answer

6p + 50
= (6 × p) + 50
= (6 × (− 10)) + 50
= − 60 + 50
= − 10

View full question & answer→

Question 73 Marks

If $m=-8$, evaluate : $\frac{ m ^2}{4}$

Answer

$\frac{ m ^2}{4}$
$=\frac{ m \times m }{4}$
$=\frac{(-8)^2}{4}$
$=\frac{(-8) \times(-8)}{4}$
$=\frac{64}{4}$
$=16$

View full question & answer→

Question 83 Marks

If m $= − 8$, evaluate:
$m^2 + 9m$

Answer

$m^2 + 9m$
$= (m \times m) + (9 \times m)$
$= (− 8 \times − 8) + (9 \times (− 8))$
$= 64 + (− 72)$
$= 64 − 72$
$= − 8$

View full question & answer→

Question 93 Marks

If $x = − 6$, evaluate:
$3x^2 + 8x$

Answer

$3x^2 + 8x$
$= (3 \times x \times x) + (8 \times x)$
$= (3 \times (− 6) \times (− 6)) + (8 \times (− 6))$
$= − 108 + (− 48)$
$= 60$

View full question & answer→

Question 103 Marks

If $a=-10$, evaluate : $\frac{1}{5} \times a ^2$

Answer

$\frac{1}{5} \times a ^2$
$=\frac{1}{5} \times( a \times a )$
$=\frac{1}{5} \times(-10) \times(-10)$
$=\frac{1}{5} \times 100$
$=20$

View full question & answer→

Question 113 Marks

If $a = − 10$, evaluate:
$a^2 + 8a$

Answer

$a^2 + 8a$
$= (a \times a) + (8 \times a)$
$= (− 10 \times (− 10)) + (8 \times (− 10))$
$= 100 + (− 80)$
$= 100 − 80$
$= 20$

View full question & answer→

Question 123 Marks

Find the average $(A)$ of four quantities $p, q, r$ and s. If $A = 6, p = 3, q = 5$ and $r = 7;$ find the value of $s.$

Answer

Given, average of four quantities $(A)=6$ and $p=3, q=5, r=7$ and $s= ?$
$\therefore A =\frac{ p + q + r + s }{4}$
$\Rightarrow 6=\frac{3+5+7+ s }{4}$
$\Rightarrow 6 \times 4=15+ s$
$\Rightarrow s =24-15$
$\Rightarrow s =9$

View full question & answer→

MATHS [3 marks sum]

Take a timed test