If the one for $175 is 10% off, that means Fiana pays 90% of the price
175 * 0.9 = $157.50
It is too expensive because 157.50 is more than the 150 Fiana has.
The second bike for $225 is 35% off which means Fiana pays 65% of the price.
225 * 0.65 = $146.25
She CAN afford the bike for $225
