Answer:
£320
Step-by-step explanation:
Chen receives £20 - £4 he spends on fuel is £16
The equation is 16 x how many gardens
2 gardens mowed would be £32
4 would be £64
6 would be £96
8 would be £128
10 would be £160
12 would be £192
14 would be £224
16 would be £256
18 would be £288
20 would be £320