A. The point estimate of μ1 − μ2 is calculated using the value of x1 - x2, therefore:
μ1 − μ2 = x1 – x2 =
7.82 – 5.99
μ1 − μ2 = 1.83
B. The formula for
confidence interval is given as:
Confidence interval
= (x1 –x2) ± z σ
where z is a value
taken from the standard distribution tables at 99% confidence interval, z =
2.58
and σ is calculated
using the formula:
σ = sqrt [(σ1^2 /
n1) + (σ2^2 / n2)]
σ = sqrt [(2.35^2 /
18) + (3.17^2 / 15)]
σ = 0.988297
Going back to the
confidence interval:
Confidence interval
= 1.83 ± (2.58) (0.988297)
Confidence interval
= 1.83 ± 2.55
Confidence interval
= -0.72, 4.38
2 because 1+1=2 and that’s why
The answer is x = 9, hope this helps- mark brainliest if you can please thanks
Step-by-step explanation:
I think you mean triangle XYZ. and angle XYZ.
so, the angle at Y is 90°.
that makes XZ the Hypotenuse (baseline opposite of the 90° angle) of the right-angled triangle.
so, we can actually use Pythagoras (we don't need the area of the triangle to solve) :
13² = 12² + YZ²
169 = 144 + YZ²
25 = YZ²
YZ = 5 cm
just to check - the area of this triangle is (remember, it is a right-angled triangle, so XY and YZ serve also as baseline and height) :
area = 12 × 5 / 2 = 60/2 = 30 cm²
correct, it fits.
