Two more math problems?

Question

Can you help me with these?

1) Solve the formula f= y(g+q)/10 for the variable q

2) A monthly water bill in a certain city is calculated by using the formula n= 6500c-29400 / 6

where n is the number of gallons used and C is the monthly cost. Solve for C and compute the bill for quantity of 1600 gallons

Please help me out here.

Answer 1

f= y(g+q)/10 for the variable q

10f = gy + qy

10f-gy = qy

so (10f-gy)/ y = q

n= 6500c-29400 / 6

1600 =  6500c-29400 / 6

9600 =  6500c-29400

9600+29400 = 6500c

39000= 6500c

39000/6500 = 6=c

Answer 2

1) f=y(g+q)/10

Multiply both sides by 10

10f=y(g+q)

Divide both sides by y

(10f)/y=g+q

subtract g from both sides

((10f)/y)-g=q

2) n=(6500c-29400)/6  (I'm assuming that's what you meant since you could have just evaluated 29400/6

Multiply by 6

6n=6500c-29400

Add 29400

6n+29400=6500c

Divide by 6500

(6n+29400)/6500=c

Next, to find the bill, we just plug 1600 in for n

(6(1600)+29400)/6500=6 dollars.