Answer: 160 plates.
Explanation:
The woman bought N plates for GH€ 150.00
4 of the plates where broken, so she has N - 4 plates to sell.
She sold each one of the N - 4 plates for GH€ 1, then after all the N- 4 plates were sold, the total money that she has is:
(N - 4)*GH€1 = GH€ (N - 4)
And the total profit (profit is the difference between the final amount of money that she gets, and the initial payment) is GH€ 6, then we have that:
GH€ (N - 4) - GH€ 150.00 = GH€ 6
ignoring the units, we have:
N - 4 - 150 = 6.
N = 6 + 154 = 160.
She bought 160 plates.