Find the triplicate ratio of $7:5$.

The sum of three numbers is $98$. If the ratio of the first to the second is $2:3$ and that of the second to the third is $5:8$,then the second number is:

The sides of a triangle are in the ratio $\frac{1}{2}: \frac{1}{3}: \frac{1}{4}$ and its perimeter is $104 \, cm$. The length of the longest side (in $cm$) is:

What will be the inverse ratio of $17: 19$?

If $6 A = 11 B = 7 C$,find $A : B : C$.

The ratio of the ages of the father and mother was $11: 10$ when their son was born. The ratio of the ages of the father and mother will be $19: 18$ when the son is twice his present age. What is the ratio of the present ages of the father and mother?