Question

Tony has $727.29 in his checking account. He must maintain a $500 balance to avoid a fee. He wrote a check for $248.50 today. Write and solve an inequality to solve for the least amount of money he needs to deposit to avoid a fee.

Answer 1

Let's say the least amount of money is "x", therefore whatever "x" is, it has to be "greater than or equals to 500", thus x ⩾ 500.

so, let's add "x" to the current balance including debts.

$\bf x\ge 500 \\\\\\ \stackrel{minimum}{x}+\stackrel{current}{727.29}-\stackrel{\textit{cheque for payment}}{248.50}\ge 500\implies x+478.79 \ge 500 \\\\\\ x\ge 500-478.79\implies x\ge 21.21$