the incubation time for rhode island red chicks is normally distributed with mean of 30 days and standard deviation of approximately 2 days. if 1000 eggs are being incubated, how many chicks do we expect will hatch in 24 to 26 days?

Guest Mar 5, 2015

#1**+5 **

30-3*2=24 so 24 is 3 standard deviations below the mean

30-3*3-26 so 26 is 2 standard deviations below the mean

Prob of being in this area is approx (99.7-95)/2 percent

$${\frac{\left({\mathtt{99.7}}{\mathtt{\,-\,}}{\mathtt{95}}\right)}{{\mathtt{2}}}} = {\frac{{\mathtt{47}}}{{\mathtt{20}}}} = {\mathtt{2.35}}$$ percent

$${\frac{{\mathtt{2.35}}}{{\mathtt{100}}}}{\mathtt{\,\times\,}}{\mathtt{1\,000}} = {\frac{{\mathtt{47}}}{{\mathtt{2}}}} = {\mathtt{23.5}}$$

23.5 chick. I suppose I should round that to approx 24 chicks. :)

Melody
Mar 5, 2015