The scale factor would be 3.5
Fractions are basically divisions.
Ex. 2/4 = 1/2
And whole numbers like 10, get greater when raised to an exponent.
Ex. 10^2 = 100
If they saved £29 all together, and if each of them saved the same amount,
then each saved £29/4 = £7.25 or £7 and 25p.
(Before decimalization in 1971, £7.25 would have been £7 and 5s .)
Identity property of addition