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Help on this maths question

"Arthur Weekly sold two quality used cars for £9999 each. On one he made a 10% profit and on the other a 10% loss. What was his overall profit or loss over the two transactions?"
The answer's supposed to be a loss of £202 but I can't get it, help pls?
Original post by selenacxoxo
"Arthur Weekly sold two quality used cars for £9999 each. On one he made a 10% profit and on the other a 10% loss. What was his overall profit or loss over the two transactions?"
The answer's supposed to be a loss of £202 but I can't get it, help pls?


To work out the 10% profit, you have to do 9999/1.1=9090 Then do 9999-9090 to get the profit which it 909 pounds. Afteer that you know he makes a 10% loss on one so 9999 pounds is 90% of the original price of the car.. Imagine the original price of the care he sold at a loss os 'x'. that would mean that 0.9x=9999. So 9999/0.9 would give the original price of the car, 11110 pounds. 9999-11110=-1111 loss. 909+-1111=-202 pound profit.
Reply 2
Original post by selenacxoxo
"Arthur Weekly sold two quality used cars for £9999 each. On one he made a 10% profit and on the other a 10% loss. What was his overall profit or loss over the two transactions?"
The answer's supposed to be a loss of £202 but I can't get it, help pls?


Okay so basically do what the other person had said, but I'd like to simplify this myself...
Lets call the car which he had profited 10 % = A :
£9999 = 10 + 100 = 110 %
£x = 100 %
To find 100% = (9999 x 100) / 110
Which gives = £9090 (Original cost)
From this we can see he has earned a profit of (9999-9090) = £909 (Profit)

Now let's look at the car where he had a loss of 10 % =Car B
£9999 = 100 - 10 = 90 %
£x = 100 %
To find 100 % = ( 9999 x 100 ) / 90
= £11110 (Original cost)
The loss here is 11110 - 9999 = £1111 (Therefore this is the amount lost)

To find the overall loss or profit:
909-1111 = -£202
Reply 3
Thanksssss, this helped a lot
Worked solution

1. Recall that Total Profit = Total Revenue - Total Costs
2. Recall that Losses = a negative Profit
3. 10% is profit, so 110100 \frac{110}{100}\ * cost of car is what the first car sold for.
4. 10% is loss, so 90100 \frac{90}{100}\ * cost of car is what the second car sold for.

110100 \frac{110}{100}\ * cost of first car = £9,999 revenue
90100 \frac{90}{100}\ * cost of second car = £9,999 revenue

the cost of the first car is GBP 9,999110100\frac{GBP\ 9,999}{\frac{110}{100}} = GBP 9,9991.1\frac{GBP\ 9,999}{1.1} = £9,090

the cost of the second car is GBP 9,99990100\frac{GBP\ 9,999}{\frac{90}{100}} = GBP 9,9990.9\frac{GBP\ 9,999}{0.9} = £11,110


5. The profit on the first car = Total Revenue - Total Costs = £9,999 - £9,090 = £909
6. The profit on the second car = Total Revenue - Total Costs = £9,999 - £11,110 = - £1,111

Total Profit = £909 + (-£1,111) = - £202

EDIT - I'm giving up trying to make it this post look pretty.
(edited 7 years ago)

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