If Sandra mixes <em>x</em> L of 65% solution with <em>y</em> L of 90% solution, then the resulting mixture has a total volume of
<em>x</em> + <em>y</em> = 500
litres, and it contains
0.65<em>x</em> + 0.90<em>y</em> = 0.75 (500) = 375
litres of alcohol.
Solve the first equation for <em>y</em> :
<em>y</em> = 500 - <em>x</em>
<em />
Substitute this into the second equation and solve for <em>x</em> :
0.65<em>x</em> + 0.90 (500 - <em>x</em>) = 375
0.65<em>x</em> + 450 - 0.90<em>x</em> = 375
75 = 0.25<em>x</em>
<em>x</em> = 300
Solve for <em>y</em> :
<em>y</em> = 500 - 300
<em>y</em> = 200
So, Sandra should mix 300 L of 65% solution with 200 L of 90% solution.
Answer:
z(s) is in the rejection region. We reject H₀. We dont have enought evidence to support that the cream has effect over the recovery time
Step-by-step explanation:
Sample information:
Size n = 100
mean x = 28,5
Population information
μ₀ = 30
Standard deviation σ = 8
Test Hypothesis
Null Hypothesis H₀ x = μ₀
Alternative Hypothesis Hₐ x < μ₀
We assume CI = 95 % then α = 5 % α = 0,05
As the alternative hypothesis suggest we should develop a one tail-test on the left ( we need to find out if the cream have any effect on the rash), effects on the rash could be measured as days of recovery
A z(c) for 0,05 from z-table is: z(c) = - 1,64
z(s) = ( x - μ₀ ) / σ/√n
z(s) = ( 28,5 - 30 ) / 8/√100
z(s) = - 1,5 * 10 / 8
z(s) = - 1,875
Comparing z(s) and z(c)
|z(s)| < |z(c)| 1,875 > 1,64
z(s) is in the rejection region. We reject H₀. We dont have enought evidence to support that the cream has effect over the recovery time
Answer:
40 square metres
Step-by-step explanation:
The shaded region is of a triangle, whose area is denoted by: A = (1/2) * b * h, where b is the base and h is the height.
Since the left figure is a square with side lengths 10, we know that the height of the triangle is also 10 metres. The right figure is a rectangle with length 4. Since the total base length of the entire figure is 18 and the base of the square is 10, then the width of the rectangle is 18 - 10 = 8 metres.
This width is also the base of the triangle, so b = 8.
Now plug these values into the equation:
A = (1/2) * b * h
A = (1/2) * 8 * 10 = (1/2) * 80 = 40
The area is 40 square metres.
Answer:
it is congruent by SAS axiom
So go with option A
Congruent -SAS
Hope it will help :)❤
Answer:
2/5
Step-by-step explanation:
