The fourth proportional to $5, 8, 15$ is

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

If $0.75 : x :: 5 : 8,$ then $x$ is equal to

$A$ mixture contains alcohol and water in the ratio of $12: 5$. On adding $14 \text{ litres}$ of water,the ratio of alcohol to water becomes $4: 3$. The quantity of alcohol in the mixture is (in $\text{litres}$):

Three containers have volumes in the ratio $3:4:5$. They are full of mixtures of milk and water. The mixtures contain milk and water in the ratio of $4:1$,$3:1$,and $5:2$ respectively. The contents of all these three containers are poured into a fourth container. The ratio of milk and water in the fourth container is

Three numbers are in the ratio $2:5:7$. The sum of the smallest and largest numbers equals the sum of the second number and $16$. What is the smallest number?