Maths taxation

Deduction:
1)Approved charitable donation:
Not less than $100
Restricted to 25% of the income

2)Expenses of self-education paid:
Max.deduction40000

3)Elderly residential care expenses paid:
Max.deduction60000

4)Home Loan interest paid:
Max.deduction150000

5)Contributions to Mandatory Provident Fund Scheme (MPFS):
Max.deduction12000
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Allowance:
1)Basic allowance
$100000

2)Married person's allowance
$ 200000

3)Child allowance(for each of the 1st to 9th child)
$30000

4)Dependent brother/sister allowance
$30000


5)Dependent parent/grandparent allowance
$30000

6)Additional dependent parent/grandparent allowance
$30000

7)Single parent allowance
$100000

8)Disabled dependent allowance
$60000
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Net chargeable income/$

On the first 30000
Rate 2% Tax/$ 600

On the next 30000
Rate 8% Tax/$ 2400

On the next 30000
Rate 14% Tax/$ 4200

Remainder
Rate 20% ------

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PLZ Help me to calculate~ OR tell me how to do~


The follwing are the particulars and the income of the Chan family in the year of assessment 2004-2005.
Income of Mr.Lee $480000
Income of Mrs.Lee nil
Donation $4000
Contribution to MPFS $24000
no. of children 2
no. of dependent parent 1


If Mr. and Mrs Chan elect Joint Assessment,find
(a)the net chargeable income of Mr.chan
(b)the tax payable by the Chan family.