Question

write and solve a proportion to answer the question. (section 6.3)

1. what percent of 15 is 6?
2. 35 is what percent of 25?
3. what number is 40% of 50?
4. 0.5% of what number is 5?

Explanation:

Question 11: What percent of 15 is 6?

Step 1: Define the proportion

Let \( x \) be the percentage. We know that \(\frac{x}{100}=\frac{6}{15}\) (since "what percent" is \( x \) out of 100, and 6 is the part of 15).

Step 2: Solve for \( x \)

Cross - multiply: \( 15x = 6\times100 \)
\( 15x=600 \)
Divide both sides by 15: \( x=\frac{600}{15}=40 \)

Step 1: Define the proportion

Let \( x \) be the percentage. So, \(\frac{x}{100}=\frac{35}{25}\) ( \( x \) percent of 100 is equivalent to 35 being the part of 25).

Step 2: Solve for \( x \)

Cross - multiply: \( 25x = 35\times100 \)
\( 25x = 3500 \)
Divide both sides by 25: \( x=\frac{3500}{25}=140 \)

Step 1: Define the proportion

Let \( x \) be the number. We have \(\frac{40}{100}=\frac{x}{50}\) (40% is 40 out of 100, and \( x \) is the part of 50).

Step 2: Solve for \( x \)

Cross - multiply: \( 100x=40\times50 \)
\( 100x = 2000 \)
Divide both sides by 100: \( x = 20 \)

Answer:

40%

Question 12: 35 is what percent of 25?