Question

write and solve an equation to answer the question.

1. 20% of 150 is what number?
2. 45 is what percent of 60?
3. 35% of what number is 35?
4. 0.8% of 150 is what number?
5. 29 is what percent of 20?
6. 0.5% of what number is 12?
7. what percent of 300 is 51?
8. 120% of what number is 102?

Explanation:

Problem 10:

Step1: Define the variable

Let the number be \( x \).

Step2: Translate the problem into an equation

20% of 150 is equal to \( x \), so \( 0.20\times150 = x \)

Step3: Solve the equation

\( 0.20\times150 = 30 \), so \( x = 30 \)

Step1: Define the variable

Let the percentage be \( p \) (expressed as a decimal).

Step2: Translate the problem into an equation

45 is \( p \) percent of 60, so \( 45 = p\times60 \)

Step3: Solve for \( p \)

Divide both sides by 60: \( p=\frac{45}{60}=0.75 \)

Step4: Convert to percentage

Multiply by 100: \( 0.75\times100 = 75\% \)

Step1: Define the variable

Let the number be \( x \).

Step2: Translate the problem into an equation

35% of \( x \) is 35, so \( 0.35x = 35 \)

Step3: Solve for \( x \)

Divide both sides by 0.35: \( x=\frac{35}{0.35}=100 \)

Answer:

The number is 30.

Problem 11: