EXAMPLE PROBLEMS:
1 . Express the following as a fraction.
a) 56%
SOLUTION:
56/100=14/25
b) 4%
SOLUTION:
4/100=1/25
c) 0.6%
SOLUTION:
0.6/100=6/1000=3/500
d) 0.08%
SOLUTION:
0.08/100=8/10000=1/1250
2.Express the following as decimals
a) 6%
SOLUTION:
6% = 6/100=0.06
b) 0.04%
SOLUTION:
0.04% = 0.04/100=0.0004
3 . Express the following as rate percent.
i).23/36
SOLUTION:
= (23/36*100) %
= 63 8/9%
ii).6 ¾
SOLUTION:
6 ¾ =27/4
(27/4 *100) % =675 %
4.Evaluate the following:
28% of 450 + 45% of 280 ?
SOLUTION:
=(28/100) *450 + (45/100) *280
= 28 * 45 / 5
= 252
5. 2 is what percent of 50?
SOLUTION:
Formula : (IS / OF ) *100 %
= 2/50 *100
= 4%
6. ½ is what percent of 1/3?
SOLUTION:
=( ½) / (1/3) *100 %
= 3/2 *100 %
= 150 %
7.What percent of 2 Metric tonnes is 40 Quintals?
SOLUTION:
1 metric tonne =10 Quintilian
So required percentage = (40/(2*10)) *100 %
= 200%
8.Find the missing figure.
i) ? % of 25 = 2.125
SOLUTION :
Let x% of 25 = 2.125
then
(x/100) *25 = 2.125
x = 2.125 * 4
= 8.5
ii) 9% of ? =6.3
SOLUTION:
Let 9 % of x = 6.3.
Then 9/100 of x = 6.3
so x = 6.3 *100/7
= 70.
9. Which is the greatest in 16 2/3 %, 2/15,0.17?
SOLUTION:
16 2/3 % = 50/3 %
= 50/3 * 1/100
= 1/6
= 0.166
2 / 15 = 0.133
So 0.17 is greatest number in the given series.
10. If the sales tax be reduced from 3 ½ % to 3 1/3 %, then what difference
does it make to a person who purchases an article with marked price of RS 8400
SOLUTION:
Required difference = 3 ½ % of 8400 - 3 1/3 % of 8400
=(7/2-10/3)% of 8400
=1/6 % of 8400
= 1/6* 1/100* 8400
= Rs 14.
11. A rejects 0.08% of the meters as defective .How many will he examine to reject 2?
SOLUTION:
Let the number of meters to be examined be x
Then 0.08% of x = 2
0.08/100*x = 2
x = 2 * 100/0.08
= 2 * 100 * 100/8
= 2500
12. 65 % of a number is 21 less than 4/5 of that number. What is the number?
SOLUTION: Let the number be x.
4/5 x - (65% of x) = 21
4/5 x - 65/100 x = 21
15 x = 2100
x = 140
