Question

Caroline has some dimes and some quarters. She has a maximum of 15 coins worth at least $2.85 combined. If Caroline has 3 dimes, determine all possible values for the number of quarters that she could have. Your answer should be a comma separated list of values.

Answer 1

Answer:

11, 12.

Step-by-step explanation:

Let q represent number of quarters.

We have been given that Caroline has a maximum of 15 coins worth at least $2.85 combined. We are also told that Caroline has 3 dimes. This means that total coins are less than or equal to 15.

We can represent this information in an inequality as:

$q+3\leq 15...(1)$

We are also told that the coins worth at least $2.85 combined. This means that the worth of all coins is greater than or equal to 2.85.

We know that each dime is worth $0.10 and each quarter is worth $0.25.

$0.25q+3(0.10)\geq 2.85...(2)$

Now, let us solve our system of inequalities.

From 1st inequality, we will get:

$q+3-3\leq 15-3$

$q\leq 12$

From 2nd inequality, we will get:

$0.25q+0.30\geq 2.85$

$0.25q+0.30-0.30\geq 2.85-0.30$

$0.25q\geq 2.55$

$\frac{0.25q}{0.25}\geq \frac{2.55}{0.25}$

$q\geq 10.2$

Upon combining our both inequalities, we will get:

$10.2\leq q\leq 12$

This means that numbers of quarters would be greater than or equal to 10.2 and less than or equal to 12.

Since we cannot have 0.2 of a coin, therefore, Caroline could have 11 or 12 quarters.