Let's solve each problem step by step:
---
Problem 1: Find the unit rate.
Given:
550 ml for 5 oranges.
Solution:
To find the unit rate, we need to determine how many milliliters (ml) are in 1 orange. We do this by dividing the total amount of liquid by the number of oranges.
\[
\text{Unit rate} = \frac{550 \, \text{ml}}{5 \, \text{oranges}}
\]
Perform the division:
\[
\frac{550}{5} = 110
\]
So, the unit rate is
110 ml per orange.
Answer:
\[
\boxed{110 \, \text{ml/orange}}
\]
---
Problem 2: Evaluate the expression for \( x = 6 \) and \( y = 4 \).
Given:
The expression is \( xy - 3y \).
Solution:
Substitute \( x = 6 \) and \( y = 4 \) into the expression:
\[
xy - 3y = (6)(4) - 3(4)
\]
First, calculate \( 6 \times 4 \):
\[
6 \times 4 = 24
\]
Next, calculate \( 3 \times 4 \):
\[
3 \times 4 = 12
\]
Now subtract:
\[
24 - 12 = 12
\]
Answer:
\[
\boxed{12}
\]
---
Problem 3: Use the following function rule to find \( f(9) \).
Given:
The function rule is \( f(x) = 2x - 9 \).
Solution:
To find \( f(9) \), substitute \( x = 9 \) into the function:
\[
f(9) = 2(9) - 9
\]
First, calculate \( 2 \times 9 \):
\[
2 \times 9 = 18
\]
Next, subtract 9:
\[
18 - 9 = 9
\]
Answer:
\[
\boxed{9}
\]
---
Problem 4: What % of 60 is 27?
Given:
We need to find what percentage 27 is of 60.
Solution:
The formula to find what percentage one number is of another is:
\[
\text{Percentage} = \left( \frac{\text{Part}}{\text{Whole}} \right) \times 100
\]
Here, the "Part" is 27, and the "Whole" is 60. Substitute these values into the formula:
\[
\text{Percentage} = \left( \frac{27}{60} \right) \times 100
\]
First, simplify the fraction \( \frac{27}{60} \):
\[
\frac{27}{60} = \frac{9}{20}
\]
Now multiply by 100:
\[
\frac{9}{20} \times 100 = 9 \times 5 = 45
\]
Answer:
\[
\boxed{45\%}
\]
---
Problem 5: Solve for \( y \).
Given:
The inequality is \( 5y - (-2) < 17 \).
Solution:
Simplify the expression \( 5y - (-2) \):
\[
5y - (-2) = 5y + 2
\]
So the inequality becomes:
\[
5y + 2 < 17
\]
Next, isolate \( y \) by subtracting 2 from both sides:
\[
5y + 2 - 2 < 17 - 2
\]
\[
5y < 15
\]
Now, divide both sides by 5:
\[
\frac{5y}{5} < \frac{15}{5}
\]
\[
y < 3
\]
Answer:
\[
\boxed{y < 3}
\]
---
Final Answers:
1. \(\boxed{110 \, \text{ml/orange}}\)
2. \(\boxed{12}\)
3. \(\boxed{9}\)
4. \(\boxed{45\%}\)
5. \(\boxed{y < 3}\)
Parent Tip: Review the logic above to help your child master the concept of free worksheet for 8th graders.
