Step-by-step explanation:
the probability is always the number of desired cases over the number of all possible cases.
in our situation we have 15 cards.
that is the total possible cases when a random card is chosen.
how many desired cases do we have ?
a number NOT a multiple of 5.
how many are there ?
it is easier to say how many numbers there are being a multiple of 5 : 5, 10, 15
so, 3 numbers out of the 15 are multiple of 5.
that means
15 - 3 = 12 numbers of the 15 are NOT multiples of 5.
so, the probability to draw a card that is not a multiple of 5 is
12/15 = 4/5 = 0.8
the information about event B and even numbers is irrelevant for the question.
Answer:
X < 9
Step-by-step explanation:
Add 1 to both sides
3 > x/3
multiply by 3 to get x by itself
9 > x
or
x < 9
7978 years
Step-by-step explanation:
A = A02^(-t/hl)
where hl = half-life.
Dividing both sides by A0 and taking the logarithm, we get
ln(A/A0) = -(t/hl)ln2
or solving for t,
t= -(hl)ln(A/A0)/ln2
note that A/A0 = 0.38
t = -(5715 yrs)[ln(0.38)/ln2]
= 7978 years
Make the two 2/1 and make the 1/3 a 3/1. Your equation should be 2/1 x 3/1, then you must simplify your answer.
