Calculate the fourth proportional to the numbers $286, 78, 1342$.

The price of a diamond is directly proportional to the square of its weight. $A$ man accidentally broke the diamond into three pieces in the ratio of $3:5:7$ and thus lost ₹ $42600$. What was the original price (in ₹) of the diamond?

The ratio of the earnings of $A$ and $B$ is $4 : 7$. If the earnings of $A$ increase by $50\%$ and those of $B$ decrease by $25\%$,the new ratio of their earnings becomes $8 : 7$. What are $A$'s earnings?

Two numbers are in the ratio of $4:9$. If the larger number is $35$ more than the smaller number,then the product of the numbers is

The ratio of $4^{3.5} : 2^{5}$ is the same as:

What will be the duplicate ratio of $2: 7$?