increasing and decreasing percentages

Question 1

a trains top speed is 140mph. after service it increases by 12%.what is its new top speed

Answer 1

156.8

Question 2

simon bought his computer for £230.a year later he sold it for 20% less.what is its price now

Answer 2

£184

Question 3

Thomas earns £22500 he recives a pay rise of 4.4% how much does he now earn

Answer 3

£23490