Step-by-step explanation:
x = price of torch
y = price of battery
x + y = £2.50
x = y + 2
->
y + 2 + y = 2.50
2y = 0.50
y = 0.25
x = y + 2 = 0.25 + 2 = 2.25
what fraction of 2.5 is 0.25 ?
it is 0.25/2.5 = 1/10
the battery is 1/10 of the total price (or 10%).
