A robotics club has 540 in its account and spends 36 on parts... | SAT Linear equations in one variable Question, Answer Explained

Question bank / Linear equations in one variable

Math · AlgebraEasy

A robotics club has $\$540$ in its account and spends $\$36$ on parts each week. If the club makes no deposits, after how many weeks will the account have $\$144$ left?

$4$

$11$

$15$

$19$

Show answer and explanation

Answer: B

After $w$ weeks the balance is $540 - 36w$ dollars. Set this equal to $144$ : $540 - 36w = 144$ . Then $36w = 396$ , so $w = 11$ .

Choice C, $\frac{540}{36} = 15$ , is the number of weeks until the account reaches $\$0$ , not $\$144$ .

Why the other choices are wrong

A. 4 weeks is how long $144 would last at $36 per week, not how long it takes the balance to fall to $144.
C. 15 is 540 divided by 36, the number of weeks until the account is empty.
D. This adds 144 to 540 instead of subtracting it before dividing by 36.

Ask Owl about this question Next question

Got it wrong? On SAT Owl, Owl looks at the answer you chose and explains the exact mistake, then gives you similar questions until it sticks. Get your predicted SAT score free, or take a free full-length practice test.