Sue has 100 dimes and quarters. If the total value of the coins is $21.40, how many of each kind of coins does she have?

Mathematics

1 answer:

Nookie1986 [14]3 years ago

3 0

Answer:

There would be 24 dimes and 76 quarters.

Step-by-step explanation:

In order to find this, start by defining the number of dimes by x and the number of quarters as y. Now we can create a system of equations. Make the first about the total number of coins.

x + y = 100

Make the second about the amount of money.

.10x + .25y = 21.40

Now we can solve using elimination by multiplying the second equation by -4 and adding through.

x + y = 100

-.40x - y = -85.60

-----------------------

.60x = 14.4

x = 24

Now we can use the amount of dimes we have to find the number of quarters.

x + y = 100

24 + y = 100

y = 76

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Ivanshal [37]

If you have 8 yellow balloons for every 12 blue balloons, then if you have 20 balloons in total, 8 out of 20 of those balloons will be yellow. Then you can set up this ratio:

$\frac{8yellow}{20total} = \frac{Xyellow}{100total}$

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3 years ago

Use Vieta's Theorem to solve the problems.

VladimirAG [237]

Answer:

The answer is -2, -17

Step-by-step explanation:

You write a system of equations

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