Given that
Value of $\mathrm{MPC}=0.9$
Initial increase in investment $=\mathit{₹}1000$ crore
So, every increase of $\mathit{₹}1$ in the income, 0.9 part of the increased income will be consumed by people.
Consumption $=\mathit{₹}0.90$
Saving $=\mathit{₹}0.10$
It is given that initial increase in investment of $\mathit{₹}1000$ will lead to change in the income by $\mathit{₹}1000$ in the first round. As MPC is 0.9 so people will consume 0.9 of the increased income i.e., $\mathit{₹}900$ there by saving $\mathit{₹}100$. In the next round due to increase in the consumption expenditure by $\mathit{₹}900$ there will be an increase in income by $\mathit{₹}900$. Then people will again spend the increased income i..., $\mathit{₹}810$ and save the rest part of the income $\mathit{₹}90$. Similarly, this process will continue and the income will go on increasing as a result of the increase in consumption. The total change in the income is $\mathit{₹}10,000$ and the change in the investment will be $\mathit{₹}1,000$.