Answer:
Step-by-step explanation:
Let
x ----> the number of minutes
y ----> the total charge in dollars
we know that
For x>700 min
so
For y=48.10
substitute
Multiply by 100 both sides
----> equation without decimals
solve for x
To find out the total minutes we need to sum
A is the correct answer coz if you substitute 22 in the place of X-5 the answer will be 17
21/25
Change to decimal:-
Divide numerator by denominator.
21/25
21 ÷ 25 = 0.84
21/25 = 0.84
Change to a percentage:-
0.84 × 100 = 84
21/25 = 0.84 = 84%
Answer:
Test statistic = 1.664
Step-by-step explanation:
The hypothesis :
H0 : μ = 47.2
H1 : μ ≠ 47.2
Given that :
Sample mean, xbar = 47
Sample size, n = 250
Standard deviation, σ = 1.9
The test statistic :
(xbar - μ) ÷ (σ/√(n))
T = (47 - 47.2) ÷ (1.9/√(250))
T = (0.2 / 0.1201665)
Test statistic = 1.664
R^2+2r-33=0 move constant to other side by adding 33 to both sides
r^2+2r=33 halve the linear coefficient, square it and add to both sides, in this case it is just one
r^2+2r+1=34 now the left side is a perfect square...
(r+1)^2=34 take the square root of both sides...
r+1=34^(1/2) subtract 1 from both sides
r=-1+34^(1/2) and -1-34^(1/2)
