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Andrew has 8.85 in dimes and quarters. The number of dimes he has is 3 more than twice his number of quarters. How many quarters does Andrew have?

2 Answers

3 votes

Answer: 19 Quarters

Explanation:

We have two variables, d and q, representing the number of dimes and quarters that Andrew has, respectively.

From the problem, we have two equations:

$0.1d + $0.25q = $8.85 (the total amount of money in dimes and quarters is $8.85)

d = 2q + 3 (the number of dimes is 3 more than twice the number of quarters)

We can substitute equation (2) into equation (1) to eliminate d:

$0.1(2q+3) + $0.25q = $8.85

Simplifying the left-hand side, we get:

$0.2q + $0.3 + $0.25q = $8.85

Combining like terms, we get:

$0.45q + $0.3 = $8.85

Subtracting $0.3 from both sides, we get:

$0.45q = $8.55

Dividing both sides by $0.45, we get:

q = 19

Therefore, Andrew has 19 quarters.

To check this answer, we can substitute q = 19 into equation (2) to find the number of dimes:

d = 2(19) + 3 = 41

Then, we can check that the total amount of money is indeed $8.85:

$0.1(41) + $0.25(19) = $4.10 + $4.75 = $8.85

So the solution is q = 19, and Andrew has 19 quarters.

User Zollie
by
8.0k points
4 votes
$8.85 = d + q
= (2q+3)+q d = dimes; q = quarters
= 4q+3
8.85 -3= 4q+3 -3
5.85 =4q
5.85/4=4q/4
1.47=q
User Davidicus
by
8.1k points