Question

Suppose babies born after a gestation period of 32 to 35 weeks have a mean weight of 2900 grams and a standard devition of 800 grams while babies born after a gestation period of 40 weeks have a mean weight of 3200 grams and a standard deviation of 485 grams. If a 32-week gestation period baby weighs 2525 grams and a 41-week gestation period baby weighs 2825 grams, find the corresponding z-scored. Which baby weighs less relative to the gestation period?

Find the corresponding z-scores. Which baby weighs relatively less? Select the correct choice below and full in the answer boxes to complete your choice.

Answer 1

Given that,

For 32-week period : mean = 2900 grams and standard deviation = 800 grams

For 41 week period : mean = 3200 grams and standard deviation = 485 grams

Z-score if a 32-week gestation period baby weighs 2525 grams is,

Z = (2525 - 2900) / 800 = -0.46875

=> Z = -0.47

and Z-score if a 41-week gestation period baby weighs 2825 grams is,

Z = (2825 - 3200) / 485 = -0.7732

=> Z = -0.77

Therefore, the z-score for if a 32-week gestation period baby weighs 2525 grams is -0.47 and z-score if a 41-week gestation period baby weighs 2825 grams is -0.77

Here, |-0.47| is less than |-0.77|

We can conclude that, a 32-week gestation period baby weighs 2525 grams is relatively less.

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