Question

A population of deer had 200 individuals. of the population dropped 15% in one year, how many deer were lost

Answer 1

A population of deer had 200 individuals and 15% were lost in one year. We can calculate the number of deer that were lost with proportion:
200 deer ------------------------100%
x deer ------------------------ 15%
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200 : x = 100 : 15
200 * 15 = 100 x
3,000 = 100 x
x = 3,000 : 100
x = 30
Answer: 30 deer were lost in one year.