Question

Two mechanics worked on a car. The first mechanic worked for 20 hours, and the second mechanic worked for 15 hours. Together they charged a total of $3225. What was the rate charged per hour by each mechanic if the sum of the two rates was $190 per hour?
First mechanic: $ per hour
Second mechanic :$ per hour
Will medal

Answer 1

@Vocaloid

Answer 2

first off, lets define our variables

f = number of hours worked by the first mechanic
s = number of hours worked by the second mechanic, with me so far?

Answer 3

yes

Answer 4

actually, let me make a quick correction

Answer 5

f = the rate charged by the first mechanic
s = the rate charged by the second mechanic

Answer 6

anyway, it says that the sum of the rates is $190

so f + s = 190, with me so far?

Answer 7

yes

Answer 8

now, it says that they charged 3225 together, total

so now, we can write another equation

first mechanic money + second mechanic money = 3225

Answer 9

so, now we can write an expression to figure out how much each mechanic made

the first mechanic worked 20 hours, so he charges:

20f

the second mechanic worked 15 hours, so he charges:

15s

Answer 10

yes

Answer 11

that gives us two equations:

f + s = 190
20f + 15s = 3225

solve for f and s

Answer 12

but how

Answer 13

start by multiplying the first equation by 20