sandy wrote:
Jacob’s weekly take-home pay is n dollars. Each week he uses \(\frac{4n}{5}\) dollars for expenses and saves the rest. At those rates, how many weeks will it take Jacob to save $500, in terms of n ?
A \(\frac{500}{n}\)
B \(\frac{2,500}{n}\)
C \(\frac{n}{625}\)
D \(\frac{n}{2,500}\)
E \(625n\)
We can also use the
INPUT-OUTPUT approach.
Let's say n =
5 (Jacob takes $5 home each week)
This means Jacob SPENDS $4 each week.
So, he SAVES $1 each week
At this rate, how many weeks are needed to save $500?
It will take
500 weeks.
So, when we INPUT n =
5, the OUTPUT (the answer to the question) is
500Now check the answer choices to see which one yields an OUTPUT of
500 when we INPUT n =
5A) 500/
5 =
100 ELIMINATE
B) 2500/
5 =
500 KEEP
C)
5/625 =
less than 1 ELIMINATE
D)
5/2500 =
less than 1 ELIMINATE
E) 625(
5) =
over 3000 ELIMINATE
Answer: B
_________________
Brent Hanneson - founder of Greenlight Test Prep