Problem
Angelo recently opened a bank account and deposits the same amount each week. After 8 weeks, he deposited \( \$ 280 \). He wants to deposit a total of \( \$ 420 \) in his account.
Solution
Step 1 ：\( \frac{280}{8} = 35 \)
Step 2 ：\( 420 - 280 = 140 \)
Step 3 ：\( \frac{140}{35} = 4 \)
