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in a recent study of 45 ninth grade students, the mean number of hours spent studying was 6.8. the standard deviation was 1.3.
a. find the best point estimate of the mean.
b. find the 90% confidence interval.
c. find the 95% confidence interval.
d. find the 99% confidence interval.

You can find it by multiplying the areas it show u

The answer is 270 cars.you can do this by making a proportional relationship. for instance, 200 is the whole we are using, so on a “number line” 200 would be over 100%. now, since he sells 35% more, add 35% to 100% to get 135% on the other side of the “number line” on the bottom half, leaving the top half empty.cross multiply 200 by 135 then divide by 100 to get your answer. i hope this , if it did, , if you don’t mind, giving me brainiest! 200/100% } 200 • 135 /100 ? /135%