R D Sharma Solutions for Chapter: Arithmetic Progressions, Exercise 7: EXERCISE 19.7

A man starts repaying a loan as first instalment of $\mathrm{₹}100$. If he increases the instalments by $\mathrm{₹}5$ every month, what amount he will pay in the ${30}^{\mathrm{th}}$ instalment?

A carpenter was hired to build $192$ window frames. The first day he made five frames and each day thereafter he made two more frames than he made the day before. How many days did it take him to finish the job?

We know that the sum of the interior angles of a triangle is ${180}^{°}$. Show that the sums of the interior angles of polygons with $3, 4, 5, 6, ...$ sides form an arithmetic progression. Find the sum of the interior angles for a $21$ sided polygon.

In a potato race $20$ potatoes are placed in a line at intervals of $4$ meters with the first potato $24$ metres from the starting point. A contestant is required to bring the potatoes back to the starting place one at a time. How far would he run in bringing back all the potatoes?

A man accepts a position with an initial salary of $\mathrm{₹}5200$ per month. It is understood that he will receive an automatic increase of $\mathrm{₹}320$ in the very next month and each month thereafter. Find his salary for the tenth month.

A man accepts a position with an initial salary of $₹5200$ per month. It is understood that he will receive an automatic increase of $₹320$ in the very next month and each month thereafter. Find his salary for the tenth month. What is his total earnings during the first year?

A man saved $\mathrm{₹}66000$ in $20$ years. In each succeeding year after the first year he saved $\mathrm{₹}200$ more than what he saved in the previous year. How much did he save in the first year?

In a cricket team tournament $16$ teams participated. A sum of $\mathrm{₹}8000$ is to be awarded among themselves as prize money. If the last place team is awarded $\mathrm{₹}275$ in prize money and the award increases by the same amount for successive finishing places, how much amount will the first place team receive?