142cm2
132cm2
122cm2
112cm2
Correct answer is B
A prism has 3 rectangular faces and 2 triangular faces and 2 rectangular faces = 10(3 + 4 + 5) = 120
Area of triangular faces = \(\sqrt{s(s - a) (s - b) (s - c)}\)
where s = \(\frac{a + b + c}{2}\)
= \(\frac{3 + 4 + 5}{2}\)
= \(\frac{12}{2}\)
= 6
Area of \(\bigtriangleup\) = \(\sqrt{6(6 - 30(6 - 4)(6 - 5)}\)
= \(\sqrt{6 \times 3 \times 2 \times 1}\) = 6
Area of triangle faces = 2 x 6 = 12cm2
Total surface area = Area of rectangular face + Area of \(\bigtriangleup\) = 120 + 12
= 132cm2
Esther was facing S 20° W. She turned 90° in the clock wise direction. What direction is she facing?
N 70o W
S 70o W
N 20o W
S 20o E
Correct answer is A
The bearing S 20° W is equivalent to a bearing of 200°.
Moving clockwise 90° ⇒ 200° + 90°
= 290°
This is equivalent to N 70° W.
A regular polygon of n sides has each exterior angle to 45o. Find the value of n
6
8
12
15
Correct answer is B
Each interior angle = \(\frac{360^o}{n}\)
45o = \(\frac{360^o}{n}\)
45on = 360o
n = \(\frac{360^o}{45}\)
= 8
11
14
16
18
Correct answer is A
Volume of cylinder = \(\pi r^2 h\)
= \(\frac{22}{7} \times 14^2\) x 14 x 18 = 22 x 28 x 18
= 11088cm3
1000cm3 = \(\frac{1}{1000}\) x 11088cm3
= 11.088
= 11
One of the factors of (mn - nq - n2 + mq) is (m - n). The other factor is?
(n - q)
(q - n)
(n + q)
(q - m)
Correct answer is C
mn - nq - n\(^2\) + mq
mn - n\(^2\) - nq + mq
(mn - n\(^2\)) (mq - nq)
n(m - n) + q(m - n)
= (n +q) (m - n)