DS - donation

[Xbond]

Hi there,

Could you give me your ELEGANT, QUICK, and EFFICIENT method to resolve (with these concepts and with finding the solution).


A certain group of car dealerships agreed to donate x dollars to a Red Cross chapter for each car sold
during a 30-day period. What was the total amount that was expected to be donated?

1) A total of 500 cars were expected to be sold.
2) 60 more cars were sold than expected, so that the total amount actually donated was $28,000

[dtweah]

Hi there,

Could you give me your ELEGANT, QUICK, and EFFICIENT method to resolve (with these concepts and with finding the solution).


A certain group of car dealerships agreed to donate x dollars to a Red Cross chapter for each car sold
during a 30-day period. What was the total amount that was expected to be donated?

1) A total of 500 cars were expected to be sold.
2) 60 more cars were sold than expected, so that the total amount actually donated was $28,000

Expected Donation= ($X/Car)(Total Number of Cars Expected to be Sold). So we need both X and number of cars sold to answer this question.

1) gives us only expected number of cars: 500x So not sufficient.

2) says that x(y+60)=28000, where y is cars expected to be sold. No suff

Combining, xy +60x=2800. Note xy= 500x in 1, and you can solve for x, don't need or have to.

Choose C.

[Xbond]

many thks

OA is C