Carcass wrote:
The cost per pound of tea and coffee were the same in June. In July, the price of coffee shot up by 200% and that of tea dropped by 90%. If in July, a mixture containing equal quantities of tea and coffee costs $4.65 for 3lbs, how much did a pound of tea cost in July?
A. $4
B. $0.1
C. $1
D. $3
E. $1.65
Kudos for the right answer and explanation
Question part of the project GRE Quantitative Reasoning Daily Challenge - (2021) EDITIONGRE - Math BookLet x = price (PER POUND) of tea in JUNE
So, Let x = price (PER POUND) of coffee in JUNE
Price of tea (PER POUND) in JULY = 0.1x (decrease by 90%).
Price of coffee (PER POUND) in JULY = 3x (increase by 200%).
In July, a mixture containing equal quantities of tea and coffee costs $4.65 for 3 lbsSo, the mixture has 1.5 lbs of tea and 1.5 lbs of coffee
We can write: (cost of 1.5 lbs of tea) + (cost of 1.5 lbs of coffee) = $4.65
So: (1.5)(0.1x) + (1.5)(3x) = 4.65
Factor: 1.5(0.1x + 3x) = 4.65
Divide both sides by 1.5 to get: 0.1x + 3x = 3.1
Simplify: 3.1x = 3.1
So,
x = 1In other words, in JUNE the price of tea and coffee were each $
1 per pound.
Since the price of tea in JULY = 0.1x, the price of tea = (0.1)(
1) = $0.1 per pound
Answer: B
Cheers,
Brent