Answer: 100 hours
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Step-by-step explanation:
The ratio
1/4 ft : 1/12 hr
is the same as the ratio
3 ft : 1 hr
after multiplying both sides by 12 to clear out the fractions. The tree's unit growth rate is 3 feet per hour. Let x be the number of hours, which means that 3x represents the height of the tree at time x. Set this equal to 300 and solve for x.
3x = 300
x = 300/3
x = 100
It takes 100 hours for the tree to go from 0 feet (aka a seedling) to 300 feet
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Notes:
- 100 hours = 100/24 = 4.167 days approximately
- 300 feet = height of 30 story building assuming each floor is 10 ft