Maths question, Oundle School past paper
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Maths question, Oundle School past paper
My son was given this question and I try to figure out but I have such a mental block!
Q) A property owner sold two terraced houses each at £99 000 each. Based on what he had paid for them, the profit on one was 10% and the loss on the other was 10%. Overall, did the property owner make a profit or loss? Calculate the amount of profit or loss.
from mark schemes, I know the answer is: A loss of £2,000 but I don't know how to calculate it.
Can you please help me.
Many thanks
Q) A property owner sold two terraced houses each at £99 000 each. Based on what he had paid for them, the profit on one was 10% and the loss on the other was 10%. Overall, did the property owner make a profit or loss? Calculate the amount of profit or loss.
from mark schemes, I know the answer is: A loss of £2,000 but I don't know how to calculate it.
Can you please help me.
Many thanks
Re: Maths question, Oundle School past paper
Classic percentage question..I'll try and explain how I have taught my son..Start with a triangle format as below..
New Number
Old Number Multiplier
The new number in the example is £99000 (the sold price of the house)
For the profit, the multiplier is 1+0.1=1.1 (100% is 1, and so 10% profit, is 0.1 as a decimal)
For the loss, the multiplier is 1-0.1=0.9 (100% is 1, therefore loss of 10% is 0.1 as a decimal and is subtracted because of reduction)
Therefore, the cost of the house prior prior to sale with 10% profit was £99000/1.1= £90000 (use the triangle)
The cost of the house prior to sale with 10% loss was £99000/0.9= £110000
So for profit, he makes £9K
and for loss, he loses £11k
Overall loss is £2k (11k-9k=2k)
This is my method and works every time;
Hope you follow the logic
New Number
Old Number Multiplier
The new number in the example is £99000 (the sold price of the house)
For the profit, the multiplier is 1+0.1=1.1 (100% is 1, and so 10% profit, is 0.1 as a decimal)
For the loss, the multiplier is 1-0.1=0.9 (100% is 1, therefore loss of 10% is 0.1 as a decimal and is subtracted because of reduction)
Therefore, the cost of the house prior prior to sale with 10% profit was £99000/1.1= £90000 (use the triangle)
The cost of the house prior to sale with 10% loss was £99000/0.9= £110000
So for profit, he makes £9K
and for loss, he loses £11k
Overall loss is £2k (11k-9k=2k)
This is my method and works every time;
Hope you follow the logic
Re: Maths question, Oundle School past paper
on the last line of the triangle, there should be a space between old number and the multiplier, the format has not been respected when I have submitted, think of a triangle with all 3 in each corner of the triangle