The johnsons pay $9.95 a month plus $.035 per min for local phone service. last month, they paid $12.75. how many minutes of local calls did they make?

Johnson's made 80 minutes of local calls

Step-by-step explanation:

The Johnson's pay $9.95 a month plus $0.035 per min for local phone service.

i.e. if Johnson's makes a local phone call for m minutes in a month then, monthly payment they have to make equals

$(9.95+0.035m)

Last month, they paid $12.75.

Let they made m minutes of local calls

then, 9.95+0.035m=12.75

0.035m=12.75-9.95

0.035m=2.8

m=2.8/0.035

m=80

Hence, Johnson's made 80 minutes of local calls

step-by-step explanation: a reaction is first order. if the initial reactant concentration is 0.0200 m, and 25.0 days later the concentration is 6.25 x 10-4 m, then its half-life is:

distance covered by pamela in 9 l of fuel = 99km

let us apply unitary method here.

distance covered by pamela in 1 l of fuel =99/9 =11 km

now let us find distance covered by pamela if she has 12 l of fuel.

distance covered in 12 l = distance covered in 1 l of fuel * 12

we know that distance covered by here in 1 l is 11 km.

so distance covered in 12 l of fuel = 11*12 = 132 km.