Answer:
The number of liters for :
Acid solution a = x = 8 liters
Acid solution b = y = 32 liters
Step-by-step explanation:
Let us represent:
The number of liters for :
Acid solution a = x
Acid solution b = y
Suppose a chemist combines a 25% acid solution and a 50% acid solution to make 40 L of 45% acid solution.
x + y = 40 ...... Equation 1
x = 40 - y
25% × x + 50% × y = 45% × 40
0.25x + 0.5y = 18...... Equation 2
We substitute, 40 - y for x in Equation 2
0.25(40 - y)+ 0.5y = 18
10 - 0.25y + 0.5y = 18
- 0.25y + 0.5y = 18 - 10
0.25y = 8
y = 8/0.25
y = 32 Liters
Solving for x
x = 40 - y
x = 40 - 32
x = 8 Liters.
Hence:
The number of liters for :
Acid solution a = x = 8 liters
Acid solution b = y = 32 liters
Answer: 
Step-by-step explanation:
Given : Sample size : n= 9
Degree of freedom = df =n-1 =8
Sample mean : 
sample standard deviation : 
Significance level ; 
Since population standard deviation is not given , so we use t- test.
Using t-distribution table , we have
Critical value = 
Confidence interval for the population mean :

90% confidence interval for the mean value will be :






Hence, the 90% confidence interval for the mean value= 
If you call
the mass of the ant and
the load, we have the equation

In fact, the mass of the ant is one tenth of the load, which is exactly what this equation states.
Since we are given the load, we simply need to plug its value in the equation to deduce the mass of the ant:

Answer:
y=650
Step-by-step explanation:
Just subtract 50 from each side
And Yes, please
The perimeter of a rectangle is twice the sum of length and width, so the sum of length and width is half the perimeter, 10 3/4 ft.
The width will be the difference between this and the length, hence 5 1/2 ft.
The area is the product of length and width.
A = length×width
A = (5.25 ft)×(5.5 ft) = 28.875 ft²
The area of the sandbox is 28 7/8 ft².