what does "within"mean?

[448018590]

I have a problem with magoosh GRE math. The question says" in a population of chickens, the average weight is 6.3 pounds, and the standard deviation is 1.2 pounds. Which of the following weights are within 1.5 units of standard deviation of the mean?"

My question is that, can I say 8.1(1.2*1.5+6.3) with in 1.5 units of standard deviation of the mean?

[tommywallach]

I don't understand your math. Within means "in the range of." 1.5 * 1.2 = 1.8. So within would be 1.8 in either direction of the mean.

-t