Answer:
Step-by-step explanation:
15). Given equation is,
Multiply the equation by 8,
Subtract 
from both the sides of the equation,
Therefore, value of the variable 'y' will be,
Answer:
x ≥ 1 (how to graph is listed below)
Step-by-step explanation:
To find where we need to plot the line, we first need to solve the inequality for x:
-2x - 3 ≤ -5
(Add three to both sides)
-2x ≤ -2
(Divide both sides by -2, but we can't forget that whenever we multiple or divide by a negative number, the sign flips!)
x ≥ 1
To graph this on the number line, you would put a dot on the 1 and fill it in completely (you fill in the dot for a "___ and equal to" sign. ex. ≥, ≤)
Then you would make an arrow from the dot to the right on the number line (this is because x must be greater than or equal to 1, so it must be facing in that direction)
I don't know what the "six-step method" is supposed to be, so I'll just demonstrate the typical method for this problem.
Let <em>x</em> be the amount (in gal) of the 50% antifreeze solution that is required. The new solution will then have a total volume of (<em>x</em> + 60) gal.
Each gal of the 50% solution used contributes 0.5 gal of antifreeze. Similarly, each gal of the 30% solution contributes 0.3 gal of antifreeze. So the new solution will contain (0.5 <em>x</em> + 0.3 * 60) gal = (0.5 <em>x</em> + 18) gal of antifreeze.
We want the concentration of antifreeze to be 40% in the new solution, so we need to have
(0.5 <em>x</em> + 18) / (<em>x</em> + 60) = 0.4
Solve for <em>x</em> :
0.5 <em>x</em> + 18 = 0.4 (<em>x</em> + 60)
0.5 <em>x</em> + 18 = 0.4 <em>x</em> + 24
0.5 <em>x</em> - 0.4 <em>x</em> = 24 - 18
0.1 <em>x</em> = 6
<em>x</em> = 6/0.1 = 60 gal
It is 48 b/c you multiply 8*12 which you get 96. then divide it by 2 or you can multiply it by 1/2.
Have a good day,
Den :)
Answer:
The probability of finding a sample mean less than 18 hours is 0.0082
Step-by-step explanation:
To find the probability of finding a sample mean less than 18 hours, we need to calculate the z-score of this sample mean 18. And the probability of finding a sample mean less than 18 hours is P(z<z(18)).
Z-score can be calculated as follows:
z(18)=
where
- X is the sample mean (18 hours)
- M is the average hours dentists spend per week on fillings (20 hours)
- s is the standard deviation (10 hours)
- N is the sample size (144)
Putting the numbers, we get:
z(18)=
Using z- table we can find that P(z<z(18)) = 0.0082
