Respuesta :

Answer:

Since x=20, y=60

We have 20 1-dollar coins and 60 50-cent coins

Step-by-step explanation:

Let the number of 1-dollar coins =x

Let the number of 50-cent coins =y

Mrs.Sanders had 80 coins

Therefore: x+y=80 ......(i)

The total amount added up to $50

Therefore: 1x+0.50y=50 .........(ii)

From equation (i), x=80-y

Substituting x=80-y into equation (ii)

1x+0.50y=50

80-y+0.50y=50

80-50=y-0.5y

30=0.5y

y=30/0.5=60

From (i)

x+y=80

x+60=80

x=80-60=20

x=20, y=60