Question

pregnant women with gestational diabetes mellitus (gdm) are at risk for long-term weight gain and subsequent development of type ii diabetes. a pilot weight loss clinical trial was conducted where women with gdm were randomized to either an active intervention using a web-based delivery or a control intervention. women were randomized at 6 weeks postpartum and then were seen at follow-up visits at 6 months and 12 months postpartum. at 12 months postpartum, women in the active group lost a mean of 0.18 lb with a standard deviation of 15.5 lbs. hint: for all parts of this problem, assume that weights can be measured exactly and no continuity correction is necessary. a button hyperlink to the salt program that reads: use salt. (a) if we assume that the change in weight from pre-pregnancy to 12 months is normally distributed, then what percent of women in the active group were at or below their pre-pregnancy weight at 12 months postpartum? (round your answer to two decimal places.) 22.36 incorrect: your answer is incorrect. % (b) at 12 months postpartum, women in the control group gained a mean of 7.8 lbs. with a standard deviation of 15.4 lbs. compared with their pre-pregnancy weight. what is the probability that a control group woman was at or below her pre-pregnancy weight at 12 months? (hint: make the same assumptions as in part (a). round your answer to four decimal places.)

1. a)The percent of women in the active group were at or below their pre-pregnancy weight at 12 months postpartum is 0.7794
b) The probability that a control group woman was at or below her pre-pregnancy weight at 12 months is 0.5520
What is Percent and Probability?
A probability is a numerical representation of the likelihood or chance that a specific event will take place. Both proportions ranging from 0 to 1 and percentages ranging from 0% to 100% can be used to describe probabilities.
A ratio or value that may be stated as a fraction of 100 is called a percentage.
a) Given,
mean = 0.2
standard deviation = 15.4
P(X < 12) = P((x-u)/s < (12 – 0.2)/15.4)
= P(z < 0.77)
= 0.77935 [since from z table]
= 0.7794
b) Given that,
in the active group, the percentage of women with weight above no more than 2lbs is
=P(X<2)=P(Z<2-(-2)/15.4)
=P(Z<0.2597)
=0.6025
hence the % of the GDM women in the program will be expected to be no more that 2lbs, above their pre-pregnancy weight
= 0.8 x 0.6025+0.2 x 0.3499
=0.5520
a) At 12 months postpartum, 0.7794 of the women in the active group were at or under their pre-pregnancy weight.
b) A control group participant’s likelihood of being at or below her pre-pregnancy weight at 12 months is 0.5520.