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KatRina [158]
3 years ago
5

Lulu tells her little brother, Jack, that she is holding 20 coins, all of which are either dimes or quarters. They have a value

of $4.10. She says she will give him the coins if he can tell her how many of each she is holding. Solve this problem for Jack.
Mathematics
1 answer:
Sunny_sXe [5.5K]3 years ago
6 0

Answer:

Lulu has 14 quarters and 6 dimes

Step-by-step explanation:

Let x be the number of dimes and y the number of quarters. The sum of quarters and dime is 20 coins. Then:

x + y = 20

We also know that the value of each dime is $ 0.10 and the value of each quarter is $0.25. The total value of the coins is $4.10. Then, the number of dimes times 0.10 plus the number of quarters times 0.25 will be 4.10:

0.10x + 0.25y = 4.10

So, we have a system of 2 equations and 2 unknowns:

x + y = 20

0.10x + 0.25y = 4.10

Let´s solve the first equation for y:

x + y = 20

subtract x from both sides

y = 20 - x

And now let´s replace y in the second equation:

0.10x + 0.25(20 - x) = 4.10

Apply distributive property

0.10x + 5 - 0.25x = 4.10

subtract 5 from both sides of the equation

-0.15x = -0.9

Divide by -0.15 both sides of the equation

x = 6

Now let´s calculate y:

y = 20 - x

y = 20 - 6 = 14

Lulu has 14 quarters and 6 dimes

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=========================================================

Explanation:

Since x-2 is a factor of f(x), this means f(2) = 0.

More generally, if x-k is a factor of p(x), then p(k) = 0. This is a special case of the remainder theorem.

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Step-by-step explanation:

Solution

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Z₀ = 0.4999999999999999/√ 0.2667 (0.7333000000000001) (0.001 +0.0005)

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The statistic value, 2.9193 is greater than the critical value 1.6448536269514722,  then we will reject the null hypothesis.

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