Joe went on a diet 6

[BTGmoderatorDC]

Joe went on a diet 6 months ago when he weighed 222 pounds. If he now weighs 198 pounds and continues to lose at the same average monthly rate, in approximately how many months will he weigh 180 pounds?

(A) 3
(B) 3.5
(C) 4
(D) 4.5
(E) 5


OA D

Source: Princeton Review

[Brent@GMATPrepNow]

Joe went on a diet 6 months ago when he weighed 222 pounds. If he now weighs 198 pounds and continues to lose at the same average monthly rate, in approximately how many months will he weigh 180 pounds?

(A) 3
(B) 3.5
(C) 4
(D) 4.5
(E) 5


OA D

Source: Princeton Review

222 - 198 = 24 pounds lost in 6 months
24/6 = 4, so Joe is losing weight at a rate of 4 pounds per month.

...in approximately how many months will he weigh 180 pounds?
A simple approach is to just list the weights.
Now: 198 lbs
In 1 month: 194 lbs
In 2 months: 190 lbs
In 3 months: 186 lbs
In 4 months: 182 lbs
In 5 months: 178 lbs

Since 180 pounds is halfway between 182 and 178, the correct answer must be 4.5 months.
Answer: D

Cheers,
Brent