Gabriella deposits $35 in a savings account at the end of each week. At the beginning of the 1st week...

1. TRANSLATE the problem information

• Given information:
  • Initial amount at beginning of 1st week: \(\$600\)
  • Weekly deposit: \(\$35\) at the end of each week
  • Need to find: Amount at the end of the 4th week

2. INFER the approach

• Since she deposits at the END of each week, by the end of the 4th week she will have made exactly 4 deposits
• Strategy: Add all deposits to the initial amount
• Formula: Final amount = Initial amount + (Number of weeks × Weekly deposit)

3. Calculate total deposits

Total deposits = 4 weeks × \(\$35\) per week = \(\$140\)

4. Calculate final amount

Final amount = \(\$600 + \$140 = \$740\)

Answer: D. 740

Why Students Usually Falter on This Problem

Most Common Error Path:

Weak TRANSLATE skill: Students misinterpret the timing and think deposits happen at the beginning of weeks, or they miscount the number of deposits (thinking it's 3 instead of 4).

For example, they might think: "If we start at the beginning of week 1, then by the end of week 4, only 3 deposits have been made." This leads to calculating \(\$600 + 3(\$35) = \$705\), but this value isn't among the choices, leading to confusion and guessing.

Second Most Common Error:

Poor TRANSLATE reasoning: Students confuse "deposit" with "withdraw" and subtract instead of add.

This leads them to calculate \(\$600 - 4(\$35) = \$600 - \$140 = \$460\), causing them to select Choice A (460).

The Bottom Line:

This problem tests careful reading and timeline tracking. The key insight is that "end of each week" for 4 weeks means exactly 4 deposits, and deposits always increase the account balance.