A25-inch wide drum is used in a marching band. what area does the top of the drum cover? round to the nearest hundredth. (use 3.14 for pi.)

Hello from MrBillDoesMath!

490.87 square inches

Discussion:

We are given that

d = 25                                  => As d(iameter) = 2 * r

2r = 25                                 => divide both sides by 2

r =  25/2 = 12.5

The area of a circle of radius "r" is Pi * r^2. Plugging in our specific numbers gives

A = Pi * (12.5)^2

  = (3.1415) * (156.25)       approximately

 =  490.87

Thank you,

MrB

85.560%

step-by-step explanation:

conditional probability is defined as:

p(a|b) = p(a∩b) / p(b)

in other words, the probability that a occurs, given that b has occurred = the probability that both a and b occur / the probability that b occurs.

in this example:

p(turns 64 | turns 44) = p(turns 64 & turns 44) / p(turns 44).

if someone turns 64, they must have already turned 44, so:

p(turns 64 | turns 44) = p(turns 64) / p(turns 44)

on page 42, we see that of the original 100,000, 94944 turn 44, and 81234 turn 64.   therefore:

p(turns 64 | turns 44) = 81234 / 94944

p(turns 64 | turns 44) = 0.85560