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# Scale drawings

## Video transcript

we're told a scale on a blueprint drawing of a house shows that 10 centimeters represents 2 meters what number of actual meters are represented by 18 centimeters on the blueprint so pause this video and see if you can figure it out so the main thing to realize is that a blueprint drawing is a scale drawing of something in the real world in this case of a house and so what we could do is set up a little bit of a table here so let's put the drawing on the left so this is the blueprint drawing and then this is the real world real world on the right and the unit that we're using the units that we're using in our drawing are centimeters so we have centimeters over here and then in the real world we're thinking in terms of meters and so let me make a little bit of a table and so we see that 10 centimeters on the drawing corresponds to 2 meters in the real world so 10 centimeters in the drawing corresponds to 2 meters in the real world then they ask us what number of actual meters are represented by 18 centimeters on the blueprint so 18 centimeters on the blueprint would correspond to what in the real world well there's several ways to approach it one way to think about it is look to go from 10 to 18 we are going to multiply by 1.8 so to go from what 10 centimeters represents in the real world to what 18 centimeters represents in the real world you would similarly multiplied by 1.8 so times 1.8 which would give us 3.6 3.6 what 3.6 meters in the real world so 3.6 meters in the real world would be what 18 centimeters on the blueprint represents let's do another example jaelyn draws a hen with scale of 2 units on her graph paper represents 6 meters 6 centimeters in the real world the hen is 16 units tall in the drawing what is the height in centimeters of the actual hand so once again pause this video and see if you can figure that out all right so let's just set up our tables again so for our table so we have our drawing and then we have the real real world and in our drawing is just these little units on our graph paper so I'll call it just that units and the real world we're thinking in terms of centimeters centimeters and so let me set up a little bit of a table here and so we know and we see that right over here from this scale we can see that two units represent six centimeters in the real world so two units in our drawing represent six centimeters in the real world and then they say the hand is 16 units tall in the drawing so it's 16 units tall in the drawing what would that represent in the real world which would be the actual height of the hand if two units represent six centimeters and now we have eight times as many units well that's going to represent eight times as many centimeters so 6 times 8 is 48 centimeters so what is the height in centimeters of the actual hand 48 centimeters 48 and we're done