Two numbers are $10\%$ and $25\%$ lesser than a third number. By what percentage must the second number be increased to make it equal to the first number (in $\%$)?

What is $15$ percent of $ 34$?

$A$ jar contains $10$ red marbles and $30$ green ones. How many red marbles must be added to the jar so that $60 \%$ of the marbles will be red?

Neha has a watch which gains $2 \%$ per hour when the temperature is in the range of $40^{\circ}C - 50^{\circ}C$ and it loses at the same rate when the temperature is in the range of $20^{\circ}C - 30^{\circ}C$. The watch runs on time in all other temperature ranges. On a sunny day,the temperature started rising from $8$ $a.m.$ at a uniform rate of $2^{\circ}C$ per hour and during the afternoon it started falling at the same rate. Find what time will it be by the watch at $7$ $p.m.$ if at $8$ $a.m.$ the temperature was $32^{\circ}C$ and at $4$ $p.m.$ it was $40^{\circ}C$?

The price of a house increases every year by $20 \%$. If the present price is $Rs \ 720000$,then what was its price (in $Rs$) $2$ years ago?

If $A$'s income is $25 \%$ less than that of $B$,then how much per cent is $B$'s income more than that of $A$?