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Welcome to Brainfuse.

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So we've looked at ratios and now we're going to move on to rates

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So a rate actually is a type of ratio

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And this problem is going to show it makes a difference

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So

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Rates, it's also a comparison between quantities but these quantities have

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Different units of measure

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So you can see them in this problem

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Is your car fuel efficient

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The car you are driving is used or my cars used but the dealer report said I could go 250 miles

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On 12 gallons of gas which is a full tank

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If that's the case what is this cars rate of fuel consumption in miles per gallon

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So first let's look for the two quantities that it's looking for

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Okay we have 250

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And 250 miles

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And 12 gallons

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Okay, and noticed that they're both quantities but they have different units. One is measured in miles and one in Gallons.

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Okay, so now I need to set up a rate, which is just a fraction and

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Think about where you which one would you put in the numerator and which one would you put in the denominator if the questions asking

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4 miles per gallon

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The number of miles covered

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For each gallon of fuel

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So we have,

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Miles

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Covered out of every gallon so Miles the numerator gallon is the denominator

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And we plug in our quantity as you have 250 miles over 12 gallons

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And since a fraction is also a

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way of writing our division problem, we now can just divide

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To see how many miles per gallon

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So 250 divided by 12, 12 goes into 25 twice.

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Differences one, okay

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12 goes into 10, 0 times

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So the difference is 10

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Now we crossed the decimal

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Point

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Across the decimal place

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Okay,

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12 times 8 is 96

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Difference of 4 so that

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12 into 40 is 3

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So 36 and that difference is also four so that

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3 is going to repeat forever and ever so our quotient is

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20.83 repeating

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Okay, so that is the answer to this problem

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But how do we know that is fuel efficient

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Should you have a car

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That has 20.83 miles per gallon

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According to random internet searches the ideal is 40 miles per gallon

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And average is about 18

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So our 20.83 miles per gallon is a little bit above average

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But we can do better

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It will save money and the environment at least help the environment

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Okay

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So that is one rate that very important when if you have a car or thinking about getting a car

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Also certainly miles per hour to make sure you're not speeding

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And the outside of

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Cars there are you'll see rates

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Everywhere you see them cups per serving when dealing with food or cooking

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And

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Also when you're doing these practice problems or taking any kind of standardized test it's important to plan your time

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So for that you want to figure out how many minutes you have per question

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So

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If you have about 10 questions in these practice problems

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And 20 minutes to do them

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Then you can figure out that okay

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Well

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20 minutes over 10 questions that will give me 2 minutes per question

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Okay

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So go figure that out to plan your time and thank you for watching this lesson