question_answer 1)

Out of 30 students in a class, 6 like football, 12 like cricket and remaining like tennis. Find the ratio of (a) Number of students liking football to number of students liking tennis. (b) Number of students liking cricket to total number of students. TIPS Firstly, find the number of students like tennis by subtracting number of students like football and cricket from total number of students and then find the required ratio.

Answer:

                Given, total number of students in a class = 30 Number of students who like football = 6 Number of students who like cricket = 12 Then, number of students who like tennis = Total number of students - (Number of students who like football + Number of students who like cricket) \[=30-(6+12)=30-18=12\] (a) Ratio of number of students liking football to number of students liking tennis   \[\text{=}\frac{\text{Number}\,\text{of}\,\text{students}\,\text{who}\,\text{like}\,\text{football}}{\text{Number}\,\text{of}\,\text{students}\,\text{who}\,\text{like}\,\text{tennis}}=\frac{6}{12}\] \[=\frac{6\div 6}{12\div 6}=\frac{1}{2}=1:2\][\[\because \]HCF of 6 and 12 = 6] (b) Ratio of number of students liking cricket to total number of students \[\text{=}\frac{\text{Number of students who like cricket }}{\text{Total number of students}}=\frac{12}{30}\] \[=\frac{12\div 6}{30\div 6}=\frac{2}{5}\]              [\[\because \]HCF of 12 and 30 = 6]