Answer:
(-
, 4 )
Step-by-step explanation:
Given the 2 equations
3x + 8y = 28 → (1)
3x + 2y = 4 → (2)
Subtracting (2) from (1) term by term will eliminate the x- term
(3x - 3x) + (8y - 2y) = (28 - 4), that is
6y = 24 ( divide both sides by 6 )
y = 4
Substitute y = 4 into either of the 2 equations and solve for x
Substituting into (1)
3x + 8(4) = 28
3x + 32 = 28 ( subtract 32 from both sides )
3x = - 4 ( divide both sides by 3 )
x = - 
Solution is (-
, 4 )
The perimeter would be 112. That’s the answer because after you multiply 6 and 8, you’ll get 48. But you can’t forget ℎ, ℎ and . In this case is 6. So you have to plug in;
ℎ: L= 8
ℎ: N•L = 6•8 = 48
So the perimeter is;
8 + 48 + 8 + 48 = 112
Answer:
Yes, we can conclude that the population standard deviation of TV watching times for teenagers is less than 2.66
Step-by-step explanation:
H0 : σ² = 2.66²
H1 : σ² < 2.66²
X²c = (n - 1)*s² ÷ σ²
sample size, n = 40
Sample standard deviation, s = 1.9
X²c = ((40 - 1) * 1.9²) ÷ 2.66²
X²c = 140.79 ÷ 7.0756
X²c = 19.897
Using a confidence level of 95%
Degree of freedom, df = n - 1 ; df = 40 - 1 = 39
The critical value using the chi distribution table is 25.6954
Comparing the test statistic with the critical value :
19.897 < 25.6954
Test statistic < Critical value ; Reject the Null
Hence, we can conclude that the population standard deviation of TV watching times for teenagers is less than 2.66