What is 10% of 370?

1. TRANSLATE the problem information

• Given information:
  • We need to find 10% of 370
  • "Of" in mathematics means multiplication
• What this tells us: We need to convert 10% to a number we can multiply with 370

2. TRANSLATE percentage to decimal

• \(\mathrm{10\% = \frac{10}{100} = 0.1}\)
• So "10% of 370" becomes \(\mathrm{0.1 \times 370}\)

3. SIMPLIFY through multiplication

• \(\mathrm{0.1 \times 370 = 37}\)
• This calculation can be done by recognizing that multiplying by 0.1 moves the decimal point one place to the left: \(\mathrm{370 \rightarrow 37.0 = 37}\)

Answer: B. 37

Why Students Usually Falter on This Problem

Most Common Error Path:

Weak TRANSLATE skill: Students misinterpret what "10% of 370" means operationally.

Some students think "10% of 370" means "370 minus 10" and calculate \(\mathrm{370 - 10 = 360}\). This fundamental misunderstanding of percentage operations occurs when students don't recognize that "of" means multiplication, not subtraction.

This leads them to select Choice D (360).

Second Most Common Error:

Calculation confusion during SIMPLIFY: Students correctly understand they need to find 10% but make errors in the percentage conversion or multiplication.

They might calculate 90% instead of 10% (thinking \(\mathrm{370 - 37 = 333}\)) or use the wrong base number entirely. Some students might think of "10% off" scenarios from shopping and accidentally find what remains rather than what the 10% represents.

This may lead them to select Choice C (333) or Choice A (27).

The Bottom Line:

This problem tests whether students truly understand that percentages represent proportional relationships expressed through multiplication, not just memorized procedures involving the number 100.