BTGModeratorVI wrote: ↑

Tue Mar 03, 2020 6:49 am

A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. If exactly 1 gallon of blue paint and 3 gallons of red paint were used, how many gallons of green paint were used?

(1) x = y
(2) z = 60

Answer: D
Source: Official Guide

Let's take each statement one by one.

(1) x = y

Since x = y, and 1 gallon of blue paint = x%, 1 gallon of green paint = y% = x%. The answer is 1 gallon of green paint. Sufficient.

(2) z = 60

Since z% = 60% = 3 gallon, we have 1 gallons = 60/3 = 20%. Thus, y% = 100 – 60 – 20 = 20%. This means that 1 gallon of green paint is used. Sufficient.

The correct answer: D

Hope this helps!

-Jay
_________________
Manhattan Review

Locations: Manhattan Review Hyderabad | GMAT Prep Bangalore | GRE Prep Chennai | Himayatnagar GRE Coaching | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.

BTGModeratorVI wrote: ↑

Tue Mar 03, 2020 6:49 am

A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. If exactly 1 gallon of blue paint and 3 gallons of red paint were used, how many gallons of green paint were used?

(1) x = y
(2) z = 60

Answer: D
Source: Official Guide

Target question: How many gallons of green paint were used?

Given: A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. 1 gallon of blue paint and 3 gallons of red paint were used.
In other words, we have:
1 gallon of BLUE paint representing x% of the mixture
3 gallons of RED paint representing z% of the mixture
? gallons of GREEN paint representing y% of the mixture

Statement 1: x = y
In other words, BLUE paint and GREEN paint comprise the same PERCENTAGE of volume in the mixture
This means the volume of BLUE paint in the mixture = the volume of GREEN paint in the mixture
Since we know there's 1 gallon of BLUE paint in the mixture, we must also have 1 gallon of GREEN paint in the mixture
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: z = 60
In other words, RED paint comprises 60% of the mixture
In other words, 3 gallons of RED paint = 60% of the mixture's TOTAL volume
It also means that 1 gallon of BLUE paint = 20% of the mixture's TOTAL volume
This means the REMAINING 20% of the mixture must be GREEN paint.
We already know that 1 gallon = 20% of the mixture
So, we must also have 1 gallon of GREEN paint in the mixture
Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Answer: D

Cheers,
Brent