Evaluate the expression 18C4

3,060

Step-by-step explanation:

Given:

18C4

nCr=n! / r!(n-r)!

=18! / 4!(18-4)!

18!=18*17*16*15*14*13*12*11*10*9*8*7*6*5*4*3*2*1

=6,402,373,705,728,000

4!=4*3*2*1

=24

(18-4)!=14!

=14*13*12*11*10*9*8*7*6*5*4*3*2*1

=87,178,291,200

18! / 4!(18-4)!

=6,402,373,705,728,000 / 24*87,178,291,200

=6,402,373,705,728,000 / 2,092,278,988,800

=3,060

answer:   b

step-by-step explanation:

x2 = 16

x can not be a negative number because 16 is positive

the only answer would be positive 8  

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