If $m : n = 3 : 2,$ then $(4m + 5n) : (4m - 5n)$ is equal to:

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

The total of the daily wages of Ram,Shyam and Mohan is $Rs. 450$. If they,respectively,spend $25 \%$,$20 \%$ and $50 \%$ of their incomes,then the ratio of their savings becomes $9:8:4$. What is the income of Ram?

Salaries of Ravi and Sumit are in the ratio $2:3$. If the salary of each is increased by $₹4000$,the new ratio becomes $40:57$. What is Sumit's present salary (in $₹$)?

What number should be added to or subtracted from each term of the ratio $17: 24,$ so that it becomes equal to $1: 2?$

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 (in $Rs.$)?