It separating the whole numbers from the fraction parts.
1 feet is 12 inches so 40 feets is 480 inches
Real locomotive is 480/16=30 times wider then the model
And then a window on the real locomotive is 30 times wider then the model.
7.) (36+42) x 24 / 2 = 936
8.) (11+14) x 10 / 2 = 125
9.) 16 x 9 / 2 = 72
10.) 21 x 32 / 2 = 336
Answer: 216 square units
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Explanation:
A common pythagorean triple you may be familiar with is the 3-4-5 right triangle. This has two legs of 3 and 4, and a hypotenuse of 5. The perimeter is 3+4+5 = 7+5 = 12. Note how this is a factor of 72.
If we multiply the perimeter (12) by 6, then 12*6 = 72. So we have scaled the triangle by a factor of 6. Each length is 6 times longer
the side length 3 becomes 3*6 = 18
the side length 4 becomes 4*6 = 24
the side length 5 becomes 5*6 = 30
The new perimeter is 18+24+30 = 42+30 = 72
The last step is to find the area. The two legs of this triangle are the base and height
area = 0.5*base*height
area = 0.5*18*24
area = 9*24
area = 216
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Or you could find the area of the 3-4-5 right triangle to get
area = 0.5*base*height = 0.5*3*4 = 6
then multiply by 36 to get 6*36 = 216. The 36 is the square of the scale factor 6 we applied above. The new lengths are 6 times longer, so the new area is 6^2 = 36 times larger.
