To calculate the sacrificing ratio of Kishore and Bimal, follow these steps:
Step 1:} Calculate the old share of Kishore and Bimal.
The old profit-sharing ratio of Kishore and Bimal is 4:3.
\[
\text{Kishore's old share} = \frac{4}{7}, \quad \text{Bimal's old share} = \frac{3}{7}.
\]
Step 2:} Calculate the new share of Kishore and Bimal.}
After Nand’s admission, Kishore and Bimal decide to share profits equally, and Nand takes $\frac{1}{4}$ of the profits.
The remaining share is:
\[
1 - \frac{1}{4} = \frac{3}{4}.
\]
Kishore and Bimal will share the remaining $\frac{3}{4}$ equally:
\[
\text{Kishore's new share} = \frac{3}{4} \times \frac{1}{2} = \frac{3}{8},
\]
\[
\text{Bimal's new share} = \frac{3}{4} \times \frac{1}{2} = \frac{3}{8}.
\]
Step 3: Calculate the sacrifice made by Kishore and Bimal.
Sacrifice = Old Share $-$ New Share
\[
\text{Kishore's sacrifice} = \frac{4}{7} - \frac{3}{8} = \frac{32}{56} - \frac{21}{56} = \frac{11}{56}.
\]
\[
\text{Bimal's sacrifice} = \frac{3}{7} - \frac{3}{8} = \frac{24}{56} - \frac{21}{56} = \frac{3}{56}.
\]
Step 4: Calculate the sacrificing ratio.
\[
\text{Sacrificing Ratio of Kishore and Bimal} = 11:3.
\]