Question

Sonji has $5.25 in nickels and dimes.The coin value can be modeled by the equation 0.10 d plus 0.05 n equals 5.25, where d represents the number of dimes and n represents the number of nickels. If Sonji has 21 dimes, how many nickels does she have?
35
42
63
105

Answer 1

Answer:

Im not sure but i think it is 42

Step-by-step explanation:

Answer 2

Answer:

Sonji has 63 nickels.

Step-by-step explanation:

Here we just have to take the given expression, and replace the amount of dime Sonji has.

So, we know that the situation is modeled by:

$0.10d+.0.05n=5.25$

Where $d$ and $n$ are dimes and nickels respectively. The model make totally sense, because each dime values 10 cents or $0.10, and each nickel values 5 cents or $0.05.

So, if Sonji has 21 dimes, we replace this in the model and solve for $n$:

$0.10d+.0.05n=5.25\\0.10(21)+0.05n=5.25\\2.1+0.05n=5.25\\0.05n=5.25-2.1\\n=\frac{3.15}{0.05}\\ n=63 \ nickels$

Therefore, according with this result, Sonji has 63 nickels.