Calculation Question! This one question is OMG DRIVING ME NUTS!

[Verbena]

Really appreciate it you can answer this one...

How many ML of a 17% zephiran chloride solution should be used to compound the following prescription?
RX:
Zephiran cl qs 17%
water- 240mL
sig: make such solution that 10mL diluted to 1 liter - 1:5,000 solution.

I keep getting 2.82mL but the answer is 28.2 mL

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[H9N9]

Final soln conc should be 1:5000 = 1gm in 5000ml = 200mg in 1000ml = 10 ml conc soln.
10ml contains 200mg 100% zephiran so 240ml contains 4800mg 100% zephiran.
17% zephiran has 17gms/17000mg in 100ml = 170mg in 1 ml.
for 4800mg required quantity is 4800mg ./. 170mg/ml= 28.2ml

or

4800mg/X ml = 170mg/ 1ml then 170X = 4800
Obviously X = 4800/170 which is Ans--28.2

Correct me if i am wrong.