Q:

Amy has $1,000 in a savings account at the beginning of the fall. She wants to have at least $500 in the account by the end of the fall. She withdraws $100 a week for living expenses. Write an inequality for the number of weeks Amy can withdraw money, and solve.A) 1000 - 100w ≤ 500; w ≥ 6 B) 1000 + 100w ≤ 500; w ≤ 5 C) 1000 + 100w ≥ 500; w ≥ 6 D) 1000 - 100w ≥ 500; w ≤ 5

Accepted Solution

A:
ANSWER:
D) 1000 - 100w [tex] \geq [/tex] 500; w [tex] \leq [/tex] 5

WHY NOT A?
Well, choice a says that you can have less than or equal to $500 ([tex] \leq 500[/tex]), but she wants $500 or more. Additionally, she can only do it for 5 weeks,  but the equation says 6 weeks (w[tex] \geq 6[/tex]).

WHY NOT B?
This choice says that she will be adding $100 a week (+100w), when the problem states, "She withdraws $100 a week". 

WHY NOT C?
This choice says that she will be adding $100 a week (+100w), when the problem states, "She withdraws $100 a week". Also, this question says that she will do it for 6 weeks when she can only do it for 5 weeks or less.