Question

scientist say 63% of all babies have brown eyes when they are born and their eye colors can change as they grow up. in 2017, allegheny county reported 12,958 babies born. how many babies are expected to have brown eyes? remember: p(brown eyes) = 63%. use the decimal form of the probability to predict the number of babies born in allegheny county with brown eyes. a 8,122 b 7,775 c 8,164

Explanation:

Step1: Convert percentage to decimal

To convert \(63\%\) to a decimal, divide by \(100\). So \(63\%=\frac{63}{100} = 0.63\).

Step2: Calculate the number of babies with brown eyes

Multiply the total number of babies (\(n = 12958\)) by the decimal - form of the probability (\(p=0.63\)).

$$12958\times0.63=(13000 - 42)\times0.63=13000\times0.63-42\times0.63$$

$$13000\times0.63 = 8190$$

$$42\times0.63=(40 + 2)\times0.63=40\times0.63+2\times0.63=25.2+1.26 = 26.46$$

$$12958\times0.63=8190-26.46=8163.54\approx8164$$

Answer:

C. 8,164