Respuesta :
0.10d + 0.25q = 7
q = d + 7
0.10d + 0.25(d + 7) = 7
0.10d + 0.25d + 1.75 = 7
0.35d = 7 - 1.75
0.35d = 5.25
d = 5.25 / 0.35
d = 15 <=== there are 15 dimes
q = d + 7
q = 15 + 7
q = 22 <== there are 22 quarters
q = d + 7
0.10d + 0.25(d + 7) = 7
0.10d + 0.25d + 1.75 = 7
0.35d = 7 - 1.75
0.35d = 5.25
d = 5.25 / 0.35
d = 15 <=== there are 15 dimes
q = d + 7
q = 15 + 7
q = 22 <== there are 22 quarters
Answer:
There are 15 dimes and 22 quarters in the jar.
Step-by-step explanation:
Deangelo has $7 worth of dimes and quarters in a jar.
Let he has d number of dimes and q number of quarters in a jar.
0.10d + 0.25q = 7 -------(1)
He has 7 more quarters than dimes.
q = d + 7 -------(2)
We replace the value of y from equation 2 in the equation 1
0.10d + 0.25(d + 7) = 7
0.10d + 0.25d + 1.75 = 7
0.35d = 7 - 1.75
0.35d = 5.25
d = [tex]\frac{5.25}{0.35}=15[/tex] dimes
Now we put this value in the equation number 2
q = 15 + 7 = 22
Therefore, number of dimes and quarters are 15 and 22 respectively.