Sally gave her brother $3.95 in quarters and dimes. If the number of quarters is 6 more than the number of dimes, how many quarters did Sally give her brother?

Respuesta :

7 dimes and 13 quarters is the exact change

Answer:  Sally gave 13 quarters to her brother.

Step-by-step explanation: Given that Sally gave her brother $3.95 in quarters and dimes and the number of quarters is 6 more than the number of dimes.

We are to find the number of quarters that Sally gave her brother.

Let, 'x' and 'y' represents the number of quarters and dimes that Sally gave her brother.

Then, according to the given information, we have

[tex]x=y+6~~~~~~~~~~~~~~~~~~~~~~~(i)\\\\\dfrac{1}{4}x+\dfrac{1}{10}y=3.95\\\\\\\Rightarrow \dfrac{5x+2y}{20}=3.95\\\\\\\Rightarrow 5x+2y=79~~~~~~~~~~~~~~~~~(ii)[/tex]

Substituting the value of 'x' from equation (i) in equation (II), we get

[tex]5(y+6)+2y=79\\\\\Rightarrow 5y+30+2y=79\\\\\Rightarrow 7y=79\\\\\Rightarrow y=7.[/tex]

From equation (i), we get

[tex]x=y+6=7+6=13.[/tex]

Thus, Sally gave 13 quarters to her brother.