Answer:
b = -57/10
Step-by-step explanation:
Let's first distribute everything out:
-8(1 + 5b) = -8 * 1 + (-8) * 5b = -8 - 40b
2(86 - 1) = 2 * 85 = 170
So, we have:
-8 - 40b - 170 = 50
-40b - 178 = 50
-40b = 50 + 178 = 228
b = -228/40 = -57/10
Thus, the answer is b = -57/10.
Hope this helps!
Is this the whole question ?
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.