Problem Solving

Can anyone please give me easy explanation for this?


Cindy has her eye on a sundress but thinks it is too expensive. It goes on sale for 15% less than the original price. Before Cindy can buy the dress, however, the store raises the new price by 25%. If the dress cost $68 after it went on sale for 15% off, what is the difference between the original price and the final price?
A) $0.00
B) $1.00
C) $3.40
D) $5.00
E) $6.80

OA: D

P*(85/100)=68$ [85/100 means 15% discount]
P=80$ original price

Final price = P*(85/100)*(125/100)=68*(125/100)=85$

Difference = 85-80 = 5$

Thank you so much !

Original price = x
15% less = 85x/100
Further in the question it is stated that 85x/100 = 68 => x = 80 (Original Price)
Price again raised by 25% on 68. Therefore new price 85

New Price (85) - Original Price (80) = 5 Answer D.

pradeepfriend2000 wrote: Cindy has her eye on a sundress but thinks it is too expensive. It goes on sale for 15% less than the original price. Before Cindy can buy the dress, however, the store raises the new price by 25%. If the dress cost $68 after it went on sale for 15% off, what is the difference between the original price and the final price?
A) $0.00
B) $1.00
C) $3.40
D) $5.00
E) $6.80

15% discount = 15/100 = 3/20.
The denominator here implies that the original price is almost certainly a multiple of 20 just a bit greater than the discounted price.
Since the discounted price = 68, the original price is probably 80:
80 less 3/20 = 80 - (3/20)80 = 80-12 = 68.
Success!
Discounted price increased by 25% = 68 + (1/4)68 = 68 + 17 = 85.
Difference between the final price and the original price = 85-80 = 5.

The correct answer is D.

Algebraically:
Since the 15% discount is equal to 3/20 of the original price, the discounted price is equal to 17/20 of the original price:
68 = (17/20)x
x = 68(20/17) = 80.
Discounted price increased by 25% = 68 + (1/4)68 = 68 + 17 = 85.
Difference between the final price and the original price = 85-80 = 5.