Which of the following correctly expresses 48 as a product of prime factors?
3 x 4 x 4
2 x 3 x 8
2 x 2 x 2 x 3 x 4
2 x 2 x 2 x 2 x 3
Correct answer is D
48 = 2 x 2 x 2 x 2 x 3
\(2\frac{1}{4}\)%
4%
5%
6%
Correct answer is B
\(I = \frac{PRT}{100}\)
\(R = \frac{100I}{PT}\)
\(R = \frac{100 \times 60}{2000 \times \frac{3}{4}}\)
\(R = \frac{6000}{1500}\)
= 4%
Solve the equation 3 + 5x - 2x2 = 0
\(-\frac{1}{2},-3\)
2, 3
-2, 3
\(-\frac{1}{2},3\)
Correct answer is D
\(3 + 5x - 2x^2 = 0\\
3 + 6x - x - 2x^2 = 0\\
3(1 + 2x) - x(1 + 2x) = 0\\
(3-x)(1+2x)=0\\
3-x = 0 \hspace{1mm}or \hspace{1mm}1+2x = 0\\
x = 3\hspace{1mm} x = -\frac{1}{2}\\
x = 3 \hspace{1mm}or\hspace{1mm} x =-\frac{1}{2}\)
Find the volume (in cm\(^3\)) of the solid shown above
100cm3
150cm3
175cm3
250cm3
Correct answer is C
Total volume = (5 x 5) x 5 + (5 x 5) x 2
= 125 + 50
= 175 cm\(^3\)
The area of a circle is 38.5cm2. Find its diameter [take \(\pi = \frac{22}{7}\)]
22cm
14cm
7cm
6cm
Correct answer is C
\(\pi r^2 = 38.5\\
\frac{}{} = r^2 = 38.5\\
r^2 = \frac{38.5 \times 7}{22}\\
r = \sqrt{12.25} = 3.5\\
diameter = 2r = 2 \times 3.5 = 7cm\)