Question Detail

A student multiplied a number by 3/5 instead of 5/3. What is the percentage error.

Answer: Option A

Explanation:

Let the number be x,
then,
\begin{aligned}
\frac{5}{3} - \frac{3}{5} = \frac{16}{15}x
\end{aligned}

Error% = \begin{aligned}
(\frac{16}{15}x * \frac{3}{5} * 100)% = 64%
\end{aligned}

1. Three candidates contested an election and received 1136, 7636 and 11628 votes respectively. What percentage of the total votes did the winning candidate got

Answer: Option C

Explanation:

Total number of votes polled = (1136 + 7636 + 11628) = 20400

So, Required percentage = 11628/20400 * 100 = 57%

2. The ratio 5:20 expressed as percent equals to

50 %
125 %
25 %
None of above

Answer: Option C

Explanation:

Actually it means 5 is what percent of 20, which can be calculated as,
(5/20)*100 = 5 * 5 = 25

3. 88% of 370 + 24% of 210 - x = 118

Answer: Option D

4. An inspector rejects 0.08% of the meters as defective, How many meters he examine to reject 2 meteres

1200
2400
1400
2500

Answer: Option D

Explanation:

It means that 0.08% of x = 2
\begin{aligned}
=> ( \frac{8}{100 \times 100} \times x) = 2 \\
=> x = \frac{2 \times 100 \times 100}{8} \\
=> x = 2500
\end{aligned}

5. Half of 1 percent written as decimal is

5
0.5
0.05
0.005

Answer: Option D

Explanation:

It will be 1/2(1%) = 1/2(1/100) = 1/200 = 0.005