From a group of 18 customers 5 are to be chosen to receive a special gift. assuming that the order is in which the customers are children is irrelevant, how many group of 5 custom it can be chosen?

objects can be chosen out of objects, when the order doesn't matter, in ways.

So, the answer is

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)