Answer:
All of these terms are dollar amounts.
Step-by-step explanation:
Here, x + y = 10 (where these numerals represent counts)
(1/2)x + (1/4)y = 4 (where (1/2), (1/4) and 4 are dollar amounts)
Let's eliminate y. To accomplish this, mult. the 2nd eq'n by-4, obtaining
-2x - y = -16, and then combining this with the 1st equation, as follows:
-2x - y = -16
x + y = 10
-------------------
-x = -6, or x = 6. This represents the number of pens purchased by Terrance.
Subbing 6 for x in the first equation, we get y = 4. This represents the number of pencils he bought.
($0.50)x + ($0.25)y = $4.00 (dollar amounts)
Answer:
81 samples
Step-by-step explanation:
According to the empirical rule :
Possible values of the sample mean is within 3 standard deviations of the population mean :
μ ± 3 sd(x) ; sd(x) = standard deviation of sampling distribution.
3 * sd(x) = 1
sd(x) = 1/3
Recall:
Standard deviation of sampling distribution, sd(x)
sd(x) = σ / sqrt(n)
1/3 = 3 / sqrt(n)
Square both sides
1/9 = 9/n
Cross multiply :
n * 1 = 9 * 9
n = 81
Answer:
2x=140
x=70
Step-by-step explanation:
Answer:
11) x = 45
12) x = 30
Step-by-step explanation:
11)
3x + x = 180
4x = 180
x = 45
12)
4x = 5x - 30
4x - 5x = -30
-x = -30
x = 30
