Me abie shows the income tax rates in Singapore, applicable from year of assessment 2017. Chargeable income Income tax rate (%) Gross tax payable (s)
First $20 000
0
0
Next $10 000
2
200
First $30 000
200
Next $10 000
3.5
350
First $40 000
550
Next $40 000
7
2800
First $80 000
3350
Next $40 000
11.5
4600
First $120 000
7950
Next $40 000
15
6000
Source: Inland Revenue Authority of Singapore
(a) Find the income tax payable if the chargeable income is
(i) $42 000,
(ii) $155 500
(b) Find the chargeable income if the income tax payable is
(i) $480,
(ii) $4600

Can someone help me?