Question

3 decrease 32 gal by 75%

1. decrease 40 in. by 35%
2. decrease 280 by 45%
3. decrease 50 by 15%

Explanation:

Step1: Understand the formula for percentage decrease

To decrease a number \( x \) by \( p\% \), we use the formula: \( \text{New Value} = x \times (1 - \frac{p}{100}) \)

Step2: Solve for "Decrease 32 gal by 75%"

Step 2.1: Identify \( x \) and \( p \)

Here, \( x = 32 \) gal and \( p = 75 \)

Step 2.2: Calculate the factor

\( 1 - \frac{75}{100}=1 - 0.75 = 0.25 \)

Step 2.3: Find the new value

\( 32\times0.25 = 8 \) gal

Step3: Solve for "Decrease 40 in. by 35%"

Step 3.1: Identify \( x \) and \( p \)

Here, \( x = 40 \) in and \( p = 35 \)

Step 3.2: Calculate the factor

\( 1 - \frac{35}{100}=1 - 0.35 = 0.65 \)

Step 3.3: Find the new value

\( 40\times0.65 = 26 \) in

Step4: Solve for "Decrease 280 by 45%"

Step 4.1: Identify \( x \) and \( p \)

Here, \( x = 280 \) and \( p = 45 \)

Step 4.2: Calculate the factor

\( 1 - \frac{45}{100}=1 - 0.45 = 0.55 \)

Step 4.3: Find the new value

\( 280\times0.55 = 154 \)

Step5: Solve for "Decrease 50 by 15%"

Step 5.1: Identify \( x \) and \( p \)

Here, \( x = 50 \) and \( p = 15 \)

Step 5.2: Calculate the factor

\( 1 - \frac{15}{100}=1 - 0.15 = 0.85 \)

Step 5.3: Find the new value

\( 50\times0.85 = 42.5 \)

Answer:

• Decrease 32 gal by 75%: \( \boldsymbol{8} \) gal
• Decrease 40 in. by 35%: \( \boldsymbol{26} \) in
• Decrease 280 by 45%: \( \boldsymbol{154} \)
• Decrease 50 by 15%: \( \boldsymbol{42.5} \)