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PROBLEM #1

Keith has $500 in a savings account at the beginning of the
summer. He wants to have at least $200 in the account by the
end of summer. He withdraws $25 a week for his cell phone
bill.
Write an inequality that represents Keith's situation.

User Kozooh
by
6.0k points

1 Answer

3 votes

Answer:

  • 500 - 25w ≥ 200

Step-by-step explanation:

Translate every verbal statement into an algebraic statement,

1. Keith has $500 in a savings account at the beginning of the summer.

  • Initial amount: 500

2. He wants to have at least $200 in the account by the end of summer.

  • Final amount ≥ 200

3. He withdraws $25 a week for his cell phone bill.

  • Call w the number of weeks
  • Withdrawls = 25w

4. Write an inequality that represents Keith's situation.

  • Create your model: Final amount = Initial amount - withdrawals ≥ 500

  • 500 - 25w ≥ 200

With that inequality you can calculate how many week will pass before his account has less than the amount he wants to have in the account by the end of summer:

  • 500 - 200 ≥ 25w
  • 300 ≥ 25w
  • 300/25 ≥ w
  • 12 ≥ w
  • w ≤ 12

That represents that he can afford spending $ 25 a week during 12 weeks to have at least $ 200 in the account.

User IVerzin
by
5.1k points