Plz quick can some one help me with these two questions also plz show working out

22a. ¼ of salary = £3600
total salary = £3600 x 4 = £14400
total amount of salary spent
= (£14400x20%) + (2/5 x £14400) + £3600
= £2880 + £5760 + £3600
= £12240

total amount saved
= £14400 - £12240
= £2160

23a. amount anwar saves = 12%
= 0.12 of his salary
amount bethany saves = 1 - 7/8
= 1/8 = 0.125 of her salary

hence, bethany saves more money each week.