Looking Back

(1) Many times in day-to-day life we compare quantities using ratios. For e.g., my income is ₹ 10000 and my friend's is ₹ 20000. Thus, my income is of my friend's income or we can say that my friend's income is my income. The ratio of my income and my friend's income is : , and the ratio of my friend's income and my income is : .

(2) When two ratios are equal they are said to be in a . The idea of proportion helps us solve various problems in our daily life.

(3) If some increase (decrease) in one quantity leads increase (decrease) in other quantity, the quantities are said to be in proportion.

(4) Ratio's can be expressed in the form of percentages. The word 'percent' means per hundred or out of every hundred. The symbol for percentage is '%'. 13 % means out of .

13% = (fraction form) = (decimal form)

(5) Percentages are used in various situations like profit and loss, discount and simple interest, etc.