I see the image you've uploaded. I'll work through the answers to the problems in the image one by one.

Problem Solutions:

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10. Mrs. Magee purchased 3 ice cream cones with a $10 bill. She received $2.86 in change. What is the price of one ice cream cone?

We can calculate the cost of the ice cream cones by subtracting the change from the total amount Mrs. Magee paid:

$10.00 - 2.86 = 7.14$

The total for 3 ice cream cones is $7.14. To find the price of one cone:

$\frac{7.14}{3} = 2.38$

Answer: $2.38 per ice cream cone.

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11. Solve the equation $\frac{7}{8} - \frac{1}{7}$:

We need a common denominator to subtract these fractions. The least common denominator between 8 and 7 is 56.

$\frac{7}{8} = \frac{49}{56}, \quad \frac{1}{7} = \frac{8}{56}$

Now subtract:

$\frac{49}{56} - \frac{8}{56} = \frac{41}{56}$

Answer: $\frac{41}{56}$

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12. The precipitation on Monday was $4 \frac{3}{4}$ inches, and on Tuesday it was $1 \frac{1}{2}$ inches. What is the combined precipitation?

Convert the mixed numbers to improper fractions:

$4 \frac{3}{4} = \frac{19}{4}, \quad 1 \frac{1}{2} = \frac{3}{2}$

We need a common denominator to add these fractions. The least common denominator is 4.

$\frac{3}{2} = \frac{6}{4}$

Now add:

$\frac{19}{4} + \frac{6}{4} = \frac{25}{4} = 6 \frac{1}{4}$

Answer: $6 \frac{1}{4}$ inches.

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14. Solve $15.6 + (-1.8)$:

This is a simple addition of a positive and negative number.

$15.6 - 1.8 = 13.8$

Answer: 13.8

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15. Solve $\frac{5}{8} + \frac{3}{4}$:

Convert $\frac{3}{4}$ to have a denominator of 8.

$\frac{3}{4} = \frac{6}{8}$

Now add:

$\frac{5}{8} + \frac{6}{8} = \frac{11}{8} = 1 \frac{3}{8}$

Answer: $1 \frac{3}{8}$

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16. Solve $2 \frac{1}{4} - (-15.2)$:

Subtracting a negative number is equivalent to adding:

$2 \frac{1}{4} + 15.2 = 2.25 + 15.2 = 17.45$

Answer: 17.45

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17. Sonia uses a gift card to purchase $5.87 of coffee each week for 3 weeks. What is the total change in the balance after 3 weeks?

Multiply the weekly cost by 3:

$5.87 \times 3 = 17.61$

The total decrease in the gift card balance is $17.61.

Answer: $-17.61$, corresponding to option A.

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18. A class is organizing a party and spends $26.38 on decorations, $78.92 on food, and $34.50 on a gift. There are 15 students. How much does each student owe?

First, find the total cost:

$26.38 + 78.92 + 34.50 = 139.80$

Now divide by 15 students:

$\frac{139.80}{15} = 9.32$

Answer: $9.32, corresponding to option D.

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Let me know if you'd like further explanations or have any additional questions.

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Follow-up questions:

1. How can you verify subtraction of fractions with different denominators?
2. What steps are involved in solving equations with negative numbers?
3. How do you convert between mixed numbers and improper fractions?
4. Why does subtracting a negative number become addition?
5. How does rounding affect calculations involving decimals?

Tip: When adding or subtracting fractions, always make sure the denominators are the same before proceeding.