MATHEMATICS MIDDLE SCHOOL

PLEASE HELPDebra saved only dimes and nickels in her bank when she last counted the coins she noticed there were twice as many dimes as nickels she had $4.75 in her bank how many dimes did she have in her bank?

A. 38
B. 24
C. 12
D. 19

Answers

Answer 1
Answer:

Answer:

A. 38

Step-by-step explanation:

Let d = number of dimes.

Let n = number of nickels.

First equation:

There are twice as many dimes as nickels. The number of dimes is 2 times the number of nickels. The first equation is:

d = 2n

Second equation:

The value of a dime is $0.10. The value of a nickel is $0.05. The value of d number of dimes is 0.1d. The value of n number of nickels is 0.05n. The total value of d dimes and n nickels is 0.1d + 0.05n. We are told the total value of her dimes and nickels is $4.75. That gives us the second equation:

0.1d + 0.05n = 4.75

We have two equations and two unknowns, so we can answer this question by solving a system of two equations in two unknowns.

d = 2n

0.1d + 0.05n = 4.75

We will use the substitution method.

Since d = 2n, replace d in the second equation with 2n.

0.1(2n) + 0.05n = 4.75

0.2n + 0.05n = 4.75

0.25n = 4.75

n = 4.75/0.25

n = 19

Now that we know the number of nickels, we use the equation d = 2n to find the number of dimes.

d = 2n

d = 2 * 19

d = 38

Answer: Debra had 38 dimes.
Answer 2
Answer:

Answer:

38

Step-by-step explanation:

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