In a survey of U. S. Adults, 16% say they have had someone take over their email accounts without their permission. You randomly select 250 U. S. Adults and asked them whether they have had someone take over their email accounts without their permission. Find the probability that the number of U. S. Adults who say they have had someone take over their email accounts without their permission is : a. At most 40 b. Less than 45 c. Exactly 48

a. At most 40

Step-by-step explanation:

If we take the survey that was done as a basis then we would use the 16% that was obtained as the number of overall US adults that have had their accounts used without their permission. Assuming that the 250 selected individuals were selected at random and without bias then those 250 would also be representative of the entire population. Therefore, we would simply need to multiply the number of selected individuals by the percentage in decimal form.

16 / 100 = 0.16

250 * 0.16 = 40

Finally, we can see that roughly 40 individuals would have had their email used without permission.

hello from mrbilldoesmath!

answer:

(7 x + 6 y) (49 x^2 - 42 x y + 36 y^2)

discussion:

the trick is to recognize that 343 = 7^3 and 216 = 6^3 and, in general,

a^3 + b^3 =   (a + b) (a^2 - a b + b^2).

in our case

343x^3+216y^3   =   (7x)^3 + (6y)^3

so take a = 7x and b = 6y in the above equation to get the answer.

you,

mrb