1.
In expressing a length of 81.472 km as nearly as possible with the three significant digits, find the percentage error
Answer: Option 'C'
Error = (81.5 - 81.472) = 0.028
Required percentage = (0.028/81.472) x 100 = 0.034%
2.
The number of 20% more than 80 is
Answer: Option 'B'
20% of 80 = (20/100) × 80 = 16
20% more than 80 = 80 + 16 = 96
3.
The population of a twon increased each year by 3% of its total at the beginning of the year. If the population on 1st january 2007 was 600000, what it on 1st January 2010?
Answer: Option 'B'
Population 1st January 2007 = 60000
Time span = 2010 - 2007 = 3 years
Increase rate = 3%
Population after 3 years
= Population in beginning x [(1 + (increasing rate)/100]time span
= 600000(1 + (3/100))3
= 600000 x (1.03)3
= 600000 x 1.092727 = 655636.2 = 655636
4.
88% of 370 + 24% of 210 - x = 118
Answer: Option 'D'
258
5.
A batsman scored 120 runs which included 3 boundaries and 8 sixes. What percent of his total score did he make by running between the wickets.
Answer: Option 'B'
Number of runs made by running = 110 - (3 x 4 + 8 x 6)
= 120 - (60)
= 60
Now, we need to calculate 60 is what percent of 120.
=> 60/120 × 100 = 50 %
6.
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'
Total number of votes polled = (1136 + 7636 + 11628) = 20400
So, Required percentage = 11628/20400 * 100 = 57%
7.
One fourth of one third of two fifth of a number is 15. What will be40% of that number
Answer: Option 'C'
(1/4) × (1/3) × (2/5) × x = 15 then x = 15 × 30 = 450
40% of 450 = 180
8.
If the radius of a circle is increased by 50%, its area is increased by
Answer: Option 'A'
125%
9.
Total number of boys and girls in a school is 150. If the number of boys is x, then girls become x% of the total number of students. The number of boys is
Answer: Option 'B'
x% of 150 = 150 - x [as x is number of boys]
=> x + (x/100) × 150 = 150
=> (5/2)x = 150
=> x = 60
10.
Half of 1 percent written as decimal is
Answer: Option 'D'
It will be 1/2(1%) = 1/2(1/100) = 1/200 = 0.005
11.
What will be the fraction of 4%
Answer: Option 'D'
4 × (1/100) = 1/25.
Friends I know it is quite simple, but trust me while solving percentage questions in Hurry we use to do these types of mistake only. So I recommend you to have a bit practise of this.