Question

DG's Plumbing and Heating charges $50 plus $65 per hour for emergency service. Bill remembers being billed just over $250 for an emergency call. How long to the nearest hour was the plumber at Bill's house?

Answer 1

Can anyone help

Answer 2

I need help with the steps to solve this

Answer 3

Looking at this, can you guess where to start?

Answer 4

No sir

Answer 5

What are the two elements that determine how much I would pay to have this plumbing company do work for me?

Answer 6

the plumbing and heating charges

Answer 7

Of course the charges, but what specifically about the charges? The problem statement gives you this info, "DG's Plumbing and Heating charges $50 plus $65 per hour for emergency service." What are the two components to the charge?

Answer 8

the house call and the emergency call?

Answer 9

Yes, but what are the "numbers" associated with that, remember that this is a math problem.

Answer 10

60 and 55

Answer 11

Yes, exactly.

Answer 12

Okay, so what does it cost JUST to have them show up, to make a house call?

Answer 13

50 dollars

Answer 14

Yes, nice work. Okay, and what if they show up AND do 1 hour of work?

Answer 15

would it be 115

Answer 16

Perfect, now, how did you get that number? Write it out mathematically.

Answer 17

I added both the 50 and 65

Answer 18

Good, so how about mathematically, how would you write that out?

Answer 19

50x+65

Answer 20

Where did the x come from?

Answer 21

What are you multiplying?

Answer 22

aw this isn't an equation

Answer 23

Technically it is an expression since there is no =

Answer 24

aw ok

Answer 25

So try it again, how would you represent the process you used mathematically?

Answer 26

can you give me an example of an expression

Answer 27

All of these are expressions.
1+2
5-2
12*2
4/1

Answer 28

ok I thought it was something different so 50+65

Answer 29

Excellent, that is exactly right. So now, how much would it cost if I had the plumber show up AND do 2 hours of work?

Answer 30

180

Answer 31

Good, can you write out, mathematically, how you got it?

Answer 32

50+130=180

Answer 33

Good, how could you break up the hourly charge?

Answer 34

50+1 hour(65)=110 50+2 hours(130)=180

Answer 35

That is a good start, what are you expressing with the 2 hours(130)?

Answer 36

the emergency service

Answer 37

What about writing it like this: 50+1*(65)=110, 50+2*(65)=180?
You are expressing that there is a $50 charge plus $65 for each hour.

Answer 38

Aw ok

Answer 39

How about if I had them come over AND do 5 hours of work?

Answer 40

would I multiply by 5

Answer 41

Yes, like you did with the 1 and 2

Answer 42

so it would be 250 and 325

Answer 43

Where did you get the 250?

Answer 44

I multiplied 50*5

Answer 45

Why?
Did you do that when you had these equations? 50+1*(65)=110, 50+2*(65)=180

Answer 46

no

Answer 47

Okay, so why would you do it now? :)

Answer 48

I wouldn't multiply I would add

Answer 49

So what would your equation look like?

Answer 50

so would I add 50 dollars 5 times and 65 dollars 5 times?

Answer 51

You have "times" in there twice, what components do you have to pay for each of the 5 hours?

Answer 52

50 and 65

Answer 53

What you are doing here is looking at what you have to pay for each hour that the service is there. Just to have them come out costs you $50, then, every hour you are charged $65. You are not charged a call-out fee every hour, you only pay that once. That is why you "add" the call-out fee.

Answer 54

Think about what is actually happening, and try to apply that to your equation to see if it fits.

Answer 55

aw ok so it's only 65

Answer 56

Yes, because that is the hourly rate, that is what you are charged for each hour they are there. You do not need to pay a call-out every hour.

Answer 57

What would the three equations look like if I asked you to tell me what it cost to have the plumbers there for 2, 3, and 4 hours?

Answer 58

I believe that you need to work on the basics a little more. This site has games and tips from pre-algebra up through calculus. Give it a look: http://www.coolmath.com/index.html