Answer:
28
Step-by-step explanation:
2y+12=3y-16
12=y-16
y=28
9 (c - 6) = 63
9c - 54 = 63
9c = 117
c = 13
Answer:
y = -(4/5)x + 7
Step-by-step explanation:
recall that the point-slope form of a linear equation is given as
y - y₁ = m (x - x₁)
in our case, we are given
slope, m = -4/5
and a point (x₁, y₁) = (5,3)
hence we simply substitute these values into the equation
y - y₁ = m (x - x₁)
y - 3 = -(4/5) (x - 5) (we will simplify this to convert to slope-intercept form)
y - 3 = -(4/5) (x) - (-4/5)(5)
y - 3 = -(4/5)x +4 (add 3 to both sides)
y = -(4/5)x +4 +3
y = -(4/5)x + 7
We first calculate the z-score corresponding to x = 1075 kWh. Given the mean of 1050 kWh, SD of 218 kWh, and sample size of n = 50, the formula for z is:
z = (x - mean) / (SD/sqrt(n)) = (1075 - 1050) / (218/sqrt(50)) = 0.81
From a z-table, the probability that z > 0.81 is 0.2090. Therefore, the probability that the mean of the 50 households is > 1075 kWh is 0.2090.
