
Consumer math
Hi,
I'm not sure of these and need them checked, kindly. Alternatives would be appreciated also :)
a.) A man sold a car for $22 000 and gained 10% on his money. How much did he pay for the car?
M => Amount paid for car
$\displaystyle 100 \% + 10 \ % = 110 \%$ (Since it's a gain, we add?)
$\displaystyle 110 \% \times \rm{M} = 22 000$
$\displaystyle \rm{M} = 22 000 \div 110 \%$
$\displaystyle \rm{M} = \$20 000$
b.) An electric iron was bought for $150 and sold for a profit 10%. What was the selling price?
$\displaystyle 100 \% + 10 \ % = 110 \%$
$\displaystyle 110 \% \times 150 = 165 $
I got this one after trial and error. My answer just coincides with the given. I don't see the reason for multiplying 1.1 by 150.
c.) In a sale the price of a pair of shoes was reduced by $\displaystyle 33 \frac13 \%$. The sale price was $30. What was the original price?
Original Price = Unknown (g)
Sale Price (Final Price) = $30
Loss % = $\displaystyle 33 \frac13\$
$\displaystyle 33 \frac13 \% = \frac13$
Relating these is the problem I'm having: $\displaystyle g  \frac13 = \$30$
$\displaystyle \frac{2}{3}g = 30$
g = 45

Re: Consumer math

Re: Consumer math
Yeah, thanks.
I don't understand the second problem (b.), as I noted in my original post. Would be glad if someone could clear it up, please!