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