# Math Help - Two problem sums

1. ## Two problem sums

1.BY selling a Coat for $630, a shopkeeper gains 5%.find the cost price of coat 2.Paul Bought a car for$960 and sold it to David at a profit of 5%.David Sold it to Tommy at a profit of 10%.Find The money paid by Tommy for the car

2. I am in 7th grade.i cant do it & i have to show it tommorow

3. If I sell something for n% profit, and I bought it for $x and sold for$y then

$\frac{y-x}{x}=\frac{n}{100}$,

which may be rearranged to give:

$y=x(1+\frac{n}{100})$.

Originally Posted by shaurya
1.BY selling a Coat for $630, a shopkeeper gains 5%.find the cost price of coat If the shop keaper gains 5% that means s/he is selling for 1.05 times what s/he paid for it. So if x is the buying price: $630=1.05 \times x$, so: $x=630/1.05$ 2.Paul Bought a car for$960 and sold it to David at a profit of 5%.David Sold it to Tommy at a profit of 10%.Find The money paid by Tommy for the car
Paul sold for:

$960\times 1.05$

David sold it for what he paid times 1.10 so he sold it for:

$960\times 1.05 \times 1.10$,

which is what tommy paid for it.

RonL

4. thnx