Percent means parts per hundred.We use the symbol % to represent it. Thus any number can be converted into percentage by dividing the number by 100.
Eg. A student secured 85 marks out of 100 in an examination, so his percentage is 85%.
Fractions, Ratios, Percents and Decimals are interrelated with each other which can be converted from one form to other.
Lets Work Out
Example- What percent of each White chocolate bar has Dark chocolate bar? Solution- Each grid above has 100 white chocolate blocks. For each white chocolate bar, the ratio of the number of dark chocolate boxes to the total number of white chocolate bars can be represented as a fraction. (i) 0 dark and 100 white. i.e. 0 per 100 or 0%.
(ii) 50 dark and 50 white. I.e. 50 per 100 or 50%.
(iii) 100 dark and 0 white i.e. 100 per 100 or 100%. |
Representing Ratio, Fraction, Percent and Decimals.
S.no |
Ratio |
Fraction |
Percent(%) |
Decimal |
1 |
1:1 |
1/1 |
100 |
1 |
2 |
1:2 |
1/2 |
50 |
0.5 |
3 |
1:3 |
1/3 |
33.333 |
0.3333 |
4 |
1:4 |
1/4 |
25 |
0.25 |
5 |
1:5 |
1/5 |
20 |
0.20 |
6 |
1:6 |
1/6 |
16.667 |
0.16667 |
7 |
1:7 |
1/7 |
14.285 |
0.14285 |
8 |
1:8 |
1/8 |
12.5 |
0.125 |
9 |
1:9 |
1/9 |
11.111 |
0.11111 |
10 |
1:10 |
1/10 |
10 |
0.10 |
11 |
1:11 |
1/11 |
9.0909 |
0.0909 |
12 |
1:12 |
1/12 |
8.333 |
0.08333 |
13 |
1:13 |
1/13 |
7.692 |
0.07692 |
14 |
1:14 |
1/14 |
7.142 |
0.07142 |
15 |
1:15 |
1/15 |
6.66 |
0.0666 |
Every percent problem has three possible unknowns, or variables : The percent, the part, or the base. In order to solve any percent problem, you must be able to identify these variables.
Look at the following examples. All three variables are known:
Example : 70% of 30 is 21 70 is the percent. 30 is the base. 21 is the part.
Example : 25% of 200 is 50 25 is the percent. 200 is the base. 50 is the part.
Example : 6 is 50% of 12 6 is the part. 50 is the percent. 12 is the base. |
Calculation Trick-
x % of y = y % of x |
Lets Work Out- Example- Prove that 10% of 30 is equal to 30% of 10. Solution- 10% of 30 = 3 30% of 10 = 3 Therefore they are equal i.e. x % of y = y % of x holds true. |