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Stanindaw
every 10 secs, 3 are born and 1 dies; net change in 10 secs = 2
2 persons every 10 secs
therefore, 1 person every 5 sec
where did i go wrong? help

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Its given that every 3 second, 1 baby is born. So every 9 seconds (not 10 second), 3 babies will be born
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Abhishekgmat87
Stanindaw
every 10 secs, 3 are born and 1 dies; net change in 10 secs = 2
2 persons every 10 secs
therefore, 1 person every 5 sec
where did i go wrong? help

Posted from my mobile device

Its given that every 3 second, 1 baby is born. So every 9 seconds (not 10 second), 3 babies will be born
that’s why we need to take the LCM, got it thanks
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In 30 seconds, people born = 10
People died = 3

Thus, in 30 seconds, the growth rate is 7 people.
For 1 person, growth rate = 30/7 seconds

Thus, the correct option is B.
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birth rate = \(\frac{1}{3}\)
death rate = \(\frac{1}{10}\)

birth rate - death rate = \(\frac{1}{3}\) - \(\frac{1}{10}\) = \(\frac{7}{30}\)
Meaning there's 7 births every 30 seconds

Can use ratio to find how long it takes for 1 birth to occur = \(\frac{30}{7}\), simplifying to 4\(\frac{2}{7}\)
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Given: In a certain country, a person is born every 3 seconds and a person dies every 10 seconds.
Asked: Therefore, the birth and death rates account for a population growth rate of one person every

Every 30 seconds, 10 perons are born and 3 are dead.
Every 30 seconds, 7 persons are added effectively.
Growth rate = 30/7 = 4 2/7 seconds / person

IMO B
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