Mult. the 2nd eqn by 6 and then add this "new" equation to the 1st given eqn:
-6x + y = -2
6x -18y = 54
--------------------
-17y = 52, or y = -52/17. Subst. this value of y into either equation to find the value of x.
Let's attack this problem using the z-score concept. The sample std. dev. here is (0.25 oz)/sqrt(40), or 0.040. Thus, the z score representing 3.9 oz. is
3.9 - 4.0
z = -------------- = -2.5
0.040
In one way or another we must find the area under the std. normal curve that lies to the left of z = -2.5. Use a table of z-scores or a calculator with built-in statistics functions. According to my TI-83 Plus calculator, that area is
0.006. One way of interpreting this that with so small a standard deviation, most volumes of coffee put into the jars are very close to the mean, 4 oz.
Are there any answer choices maybe??
Answer:
- Infinitely Many
- Distributive Property
Step-by-step explanation:
8x + 2(x - 7) = 7x + 3x - 14
8x + 2x - 14 = 7x + 3x - 14 Distributive property.
10x - 14 = 10x - 14 Combine the like terms.
-14 = -14 Subtraction.
0 = 0 Addition.
Since the statement 0 = 0 is true regardless of the value of x, there is infinitely many solutions.