If I spend f rupees from 100 rupees, the money left with me is _________ rupees.
If I spend f rupees from 100 rupees, the money left with me is 100 – f rupees.
Think of it step by step:
1) Money you start with:
\[ 100 \text{ rupees} \]
2) Money you spend:
\[ f \text{ rupees} \]
3) Money left = Money you start with − Money you spend
\[ \text{Money left} = 100 - f \]
So, the remaining money is:
\[ 100 - f \text{ rupees} \]
Quick check:
If \( f = 20 \), then
\[ \text{Money left} = 100 - 20 = 80 \text{ rupees} \]