What is 160% of 40? Four students solved this problem and their work is shown below. Choose the student whose work is correct.

Cam's work. 16 times 40 = 00 .00 + 640 = 640.
Gitana's work. 1.6 times 40 = 00. 00 + 640 = 64.0.
Naoko's work. 0.16 times 40 = 00. 00 + 640 = 6.40.
Sanjay's work. 160 times 40 = 00. 00 + 6400 = 6400.

1 answer

To find 160% of 40, we can first convert the percentage to a decimal and then multiply by 40.

  1. Convert 160% to a decimal:
    \( 160% = \frac{160}{100} = 1.6 \)

  2. Now multiply by 40:
    \( 1.6 \times 40 = 64 \)

Thus, 160% of 40 is 64.

Now, let's evaluate each student's work:

  • Cam's work: \( 16 \times 40 = 640 \) - This is correct, and it looks like he meant to say 160% is the same as 1.6, but he didn't clarify his steps correctly.

  • Gitana's work: \( 1.6 \times 40 = 64 \) - This is the correct calculation. Gitana has the correct multiplication.

  • Naoko's work: \( 0.16 \times 40 \) = 6.4 - This is incorrect, as Naoko used the wrong decimal (0.16 instead of 1.6).

  • Sanjay's work: \( 160 \times 40 = 6400 \) - This is also incorrect because he misinterpreted the percentage and did not convert it to a decimal.

Therefore, the student whose work is correct is Gitana.