Answer: 30
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Step-by-step explanation:
Let x be the height of the boat in the mural.
The actual boat has a height of 40 feet. The ratio of 40 to x is 4:3
So 40:x is the same as 4:3
We can multiply both parts of 4:3 by 10 to end up with 40:30. From here, we can see that x = 30.
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Or we can solve like this
(actual boat height)/(mural boat's height) = 4/3
40/x = 4/3
40*3 = 4x
120 = 4x
120/4 = x
30 = x
x = 30