Suppose babies born after a gestation period of 32 to 35 wee

Suppose babies born after a gestation period of 32 to 35 weeks have a mean weight of 2600 grams and a standard deviation of 800 grams while babies born after a gestation period of 40 weeks have a mean weight of 3100 grams and a standard deviation of 500 grams. If a 32-week gestation period baby weighs 3000 grams and a 40-week gestation period baby weighs 3500 grams, find the corresponding z-scores. Which baby weighs more relative to the gestation period? The 32-week gestation period baby weighs standard deviations the mean. The 40-week gestation period baby weighs standard deviations the mean (Round to two decimal places as needed.) Which baby weighs relatively more?

Solution

The 32 week gestation period baby weighs (3000-2600)/800 = 0.50 standard deviations greater than the mean.

The 40 week gestation period baby weighs (3500-3100)/500 = 0.80 standard deviations greater than the mean.

Z score for 40 week baby is 0.80, higher than 0.50

Answer: D. The baby born in week 40 does since its z-score is larger.