Question

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

Answer 1

The correct answer is D. 1000 - 100w ≥ 500; w ≤ 5. Take the starting amount, 1000, and subtract 100 “w” times (“w” is the number of weeks). This expression must be ≥ 500 since she wants to have at least $500. Solve the inequality to get the answer.

Answer 2

The answer is d. We can already eliminate b and c because we are subtracting from the original amount, not adding. It can't be A because then the amount of money she will have will be less than or equal to 500. However she wants to have money that will be at least or greater than or equal to 500 dollars. So the answer is D. I hope this helps!