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3 years ago

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The time is takes to build a skyscraper is proportional to its height and inversely proportional to the number of construction w

orkers. If it takes 10 workers 2.5 years to build a 20 story building, how long will it take 70 workers to build a 60 story building?

1 answer:

SCORPION-xisa [38]3 years ago

7 0

Answer:

$t = 1.07 years$

Explanation:

As we know that time to build is proportional to height and inversely proportional to the number of workers

so we can say that

$t = c\frac{H}{N}$

here we know that 10 workers took 2.5 years to build 20 story building

so we will have

$2.5 years = c\frac{20}{10}$

$c = \frac{2.5}{2}$

now we will have 70 workers to build 60 story building

so we have

$t = \frac{2.5}{2} \times \frac{60}{70}$

$t = 1.07 years$

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