Anne, Barry and Colin share a prize in the ratio 3 : 4 : 5 - OCR - GCSE Maths - Question 3 - 2019 - Paper 4

First, we start by determining the total parts of the prize shared by Anne, Barry, and Colin:

$3 + 4 + 5 = 12 \text{ parts}$

Next, we find out how much each person's share is. Colin's share is:

$\frac{5}{12} \text{ of the total prize}$

Colin gives $\frac{1}{3}$ of his share to charity, which can be calculated as follows:

$\frac{1}{3} \times \frac{5}{12} = \frac{5}{36} \text{ of the total prize}$

Finally, the fraction of the whole prize that Colin gives to the charity is:

$\frac{5}{36}$