To find the cost of cloth per metre, we need to use the given total length and total cost.
1. First, convert the mixed fractions to improper fractions for ease of calculation:
[tex]\[
2 \frac{1}{2} \text{ metres} = 2 + \frac{1}{2} = \frac{4}{2} + \frac{1}{2} = \frac{5}{2} \text{ metres}
\][/tex]
[tex]\[
78 \frac{3}{4} = 78 + \frac{3}{4} = \frac{312}{4} + \frac{3}{4} = \frac{315}{4}
\][/tex]
2. Now, we need to find the cost of cloth per metre by dividing the total cost by the total length:
[tex]\[
\text{Cost per metre} = \frac{\text{Total cost}}{\text{Total length}} = \frac{\frac{315}{4}}{\frac{5}{2}} = \frac{315}{4} \times \frac{2}{5} = \frac{315 \times 2}{4 \times 5} = \frac{630}{20} = 31.5
\][/tex]
Therefore, the cost of cloth per metre is ₹31.5.
