Which equation can be used to find 40 percent of 25?

StartFraction 25 divided by 1 Over 40 divided by 1 EndFraction = StartFraction 25 Over 40 EndFraction
StartFraction 100 times 4 Over 40 times 4 EndFraction = StartFraction 400 Over 16 EndFraction
StartFraction 40 times 4 Over 25 times 4 EndFraction = StartFraction 160 Over 100 EndFraction
StartFraction 40 divided by 4 Over 100 divided by 4 EndFraction = StartFraction 10 Over 25 EndFraction

1 answer

To find 40 percent of 25, you can express this mathematically as:

\[ 0.40 \times 25 \]

This can also be rewritten as a fraction:

\[ \frac{40}{100} \times 25 \]

To find the correct equation among the provided options, let's analyze each one.

  1. \( \frac{25}{\frac{1}{40}} = \frac{25}{40} \)

    • This is incorrect because it does not yield the correct value for 40% of 25.
  2. \( \frac{100 \times 4}{40 \times 4} = \frac{400}{160} \)

    • This is also incorrect because it does not reflect the calculation for 40% of 25.
  3. \( \frac{40 \times 4}{25 \times 4} = \frac{160}{100} \)

    • This simplifies to 1.6, which is actually 40% of 25. Thus, this option is valid as it correctly leads to the calculation of \( 0.40 \times 25 \).
  4. \( \frac{40}{4} \div \frac{100}{4} = \frac{10}{25} \)

    • This doesn't correspond to finding 40% of 25 correctly; it leads to a ratio instead.

The best answer that correctly represents finding 40% of 25 is:

Option 3: \( \frac{40 \times 4}{25 \times 4} = \frac{160}{100} \)

This correctly simplifies and leads to the calculation for finding 40% of 25.