Fraction of Original Price

[nycmathguy]

A dress is marked down by 20% and placed on a clearance rack, on which is posted a sign reading, “Take an extra 25% off already reduced merchandise.” What fraction of the original price is the final sales price of the dress?

A. 9/20

B. 11/20

C. 2/5

D. 3/5


I think adding is needed here.

0.20 + 0.25 = 0.45

9/20 = 0.45

I say the answer is 9/20.

 

[Country Boy]

"A dress is marked down by 20% and placed on a clearance rack, on which is posted a sign reading, “Take an extra 25% off already reduced merchandise.” What fraction of the original price is the final sales price of the dress?"

No. The "20%" and "25%" are of different quantities and cannot be added like that.

Imagine that the original price of the dress was $100. 20% of that is $20 so it is reduced to 100- 20= $80. 25% is 1/4 and 1/4 of 80 is $20 so it is reduced further to 80- 20= $60. That is 60/100= 6/10= 3/5 of the original price.