EXERCISE 12.1

If the simplest ratio of the following is $x \mathrm{cm}: y \mathrm{cm}$ then find $x:y$.

$x=40 \mathrm{cm}$ to $y=1.5 \mathrm{m}$

Out of $1800$ students in a school, $750$ opted basket ball, $800$ opted cricket and remaining opted table tennis. If a student can opt only one game, find the ratio of number of students who opted cricket to the number of students opting basketball.

Out of $1800$ students in a school, $750$ opted basketball, $800$ opted cricket and remaining opted table tennis. If a student can opt only one game, find the ratio of number of students who opted basketball to the total number of students.

Cost of a dozen pens is $\mathrm{₹}180$ and cost of $8$ ball pens is $\mathrm{₹}56.$ Find the ratio of the cost of a pen to the cost of a ball pen.

Present age of father is $42$ years and that of his son is $14$ years. Find the ratio of present age of father to the present age of son.

Present age of father is $42$ years and that of his son is $14$ years.
Find the ratio of age of the father to the age of son, when son was $12$ years old in the simplest fraction form.
 

Present age of father is $42$ years and that of his son is $14$ years. Find the ratio of
Age of father after $10$ years to the age of son after $10$ years in simplest fraction form.
 

Present age of father is $42$ years and that of his son is $14$ years.
Find the ratio of age of father to the age of son when father was $30$ years old in the simplest fraction form.