a trader buys 7 items for dollar 4.10 each for 5 items for dollar 6.40 each. he sells all of them for dollar 10 each. calculate his profit
To calculate the trader's profit, we need to determine the total cost and the total revenue.
The cost of the 7 items purchased at $4.10 each is 7 * $4.10 = $<<7*4.10=28.70>>28.70.
The cost of the 5 items purchased at $6.40 each is 5 * $6.40 = $<<5*6.40=32.00>>32.00.
The total cost is $28.70 + $32.00 = $<<28.70+32.00=60.70>>60.70.
The total revenue from selling all the items at $10 each is 7 * $10 + 5 * $10 = $70 + $50 = $<<7*10+5*10=120>>120.
The profit is calculated by subtracting the total cost from the total revenue: $120 - $60.70 = $<<120-60.70=59.30>>59.30.
Therefore, the trader's profit is $59.30.