£7.90
add the parts of the ratio 2 + 3 + 4 = 9 parts
divide £71.10 by 9 to find one part of the ratio
[tex]\frac{71.10}{9}[/tex] = £7.90 ← 1 part of the ratio
2 parts = 2 × £7.90 = £15.80 ← Paul's share
3 parts = 3 × £7.90 = £23.70 ← Colin's share
4 parts = 4 × £7.90 = £31.60 ← Brian's share
Colin receives £23.70 - £15.80 = £7.90 more than Paul
