"Linear function" means the highest degree of any term is 1.
Equation 1: degree is 2
Equation 2: degree is 2
Equation 3: degree is 1 . . . . this is your linear function
Equation 4: degree is 4
The sums range from 2 to 12 of which 6 are even out of 11 possible sums.
There are 4 multiples of 3, two of which are odd.
So the number of even sums is 6 and there are 2 unique or odd multiples of 3.
So there are a total 6+2=8 outcomes we want out of 36 possible outcomes.
The probability is then 8/36 or 2/9
$30 because you are taking away 20% of $30 and then adding back that 20%.
If you flip a coin one time, the probability to get a Head is
p = 1/2
The probability of not getting a head in a single toss is :
q = 1 - 1/2 = 1/2
Thus there is only one unique situation to get the same number of heads and tails : in 10 toss you need to get exactly five heads, it will means that the rest is the tails.
Now using Binomial theorem of probability, the probability of getting exactly x = 5 heads in a total of n = 10 tosses is :
P(X = 5) =
≈ 0.246
So the probability of that is 24,6 %
Good Luck
I believe it would be x+5^2