Find the number which,when subtracted from the terms of the ratio $12: 17$,makes it equal to the ratio $2: 3$.

₹ $1980$ is divided among $A, B$ and $C$ such that half of $A$'s part,one-third of $B$'s part,and one-sixth of $C$'s part are equal. Then $B$'s part is (in ₹):

The incomes of Gupta and Verma are in the ratio $9: 4$ and their expenditures are in the ratio $7: 3$. If each saves ₹ $2000$,then Gupta's expenditure is (in ₹):

If $(x+y):(x-y)=11:1$,find the value of $\frac{(5x+3y)}{(x-2y)}$.

If an alloy contains copper and silver in the ratio $3:7$,then the percentage quantity of silver in the alloy is

The mean proportional between $64$ and $81$ is