Answer:
P = 0.05
Step-by-step explanation:
12 months * 30 days each = 360 days
From 306 days, we have to select 8 days = 360C8 ways(Total ways)
We want each days from different month. First, we have to select 8 month from 12 month = 12C8 ways
---By selecting 8 month, we will select a days from each month. That can be done in = 30C1 * 30C1 * .................30C1 (8 ways) [From a month with 30 days, we can select a day in 30C1 ways = 30 ways]
Therefore P = Number of ways of selecting each days from different month / Total number of ways
P = 12C8 * 30^8 / 360C8
P = 495 * 656100000000 / 6469697679132645
P = 0.0501985588982791
P = 0.05
Hence the probability that each day is from a different month is 0.05
The answer is the first answer choice
Answer:
x = -3 and y = -4
x + y = -3-4 = -7
Step-by-step explanation:
-4x + 9y = -11 ------------------------------------------------------------------------(1)
-3x + 7y = -9--------------------------------------------------------------------------(2)
multiply through equation (1) by 3 and multiply through equation(2) by 4
-12x + 27y = -33 -----------------------------------------------------------------------(3)
-12x + 28y = -36 ----------------------------------------------------------------------(4)
subtract equation (1) from equation (2)
y = -3
substitute y = -3 into equation (2)
-3x + 7(-3) = -9
-3x -21 = -9
add 21 to both-side of the equation
-3x -21 + 21 = -9 + 21
-3x = 12
divide both-side of the equation by -3
-3x/-3 = 12/-3
x = -4
x = -3 and y = -4
Given that the two lines are parallel, we can assume that the two angles given are supplementary (due to them being same side interior angles)
Supplementary angles - when the sum of their degree measure is 180°
8x - 13 + 4x + 1 = 180
12x = 192
x = 16