95%
47.5%
5.26%
5%
Correct answer is D
The percentage error is \(\frac{error}{actual}\times \frac{100}{1}\%\\
=\frac{200-190}{200}\times \frac{100}{1}\\
=\frac{10}{200}\times \frac{100}{1}\% = 5\%\)
81
72
54
45
Correct answer is A
Ratio of good ones to bad ones is 5:4; If 36 is bad;
∴ the good ones = \(\frac{5\times 36}{4}=45\) oranges.
The total number of oranges is 36 + 45 = 81.
If N varies directly as M and N = 8 when M = 20 find M when N = 7
13
15
\(17\frac{1}{2}\)
\(18\frac{1}{2}\)
Correct answer is C
N ∝ M
∴N = kM where k is a constant
N = 8 when M = 20
∴ 8 = k x 20
\(k = \frac{8}{20} = \frac{2}{5}\\
∴ N = \frac{2}{5}M\\
If N = 7\\
∴ 7 = \frac{2}{5}M\\
M = \frac{35}{2} = 17\frac{1}{2}\)
15
30
35
45
Correct answer is C
Let c = no of students that offered both subjects ∴ No of students offering Economics = 65 - c No of students offering Geography = 50 - c 65 - c + c + 50 - c = 80 115 - c = 80 c = 35 35 students offer both Economics and Geography.
Evaluate \(log_{10}5 + log_{10}20\)
2
3
4
5
Correct answer is A
\(log_{10}5 + log_{10}20\\
log_{10}[5\times 20]\\
log_{10}100\\
log_{10}10^2\\
2log_{10}10=2\)