Answer:
Jessie sold x DVDs for $<u>3</u> each and then sold a board game for $<u>12</u>. Jessie made (select) $27 in her sales. How many DVDs did she sell?
She sold 5 DVDs
Step-by-step explanation:
3x+12=27
3x=15
x=5
5 DVDS
Answer:
Step-by-step explanation:
x² - 12x + a = (x + b)²
x² - 12x + a = x² + 2xb + b²
-12 = 2b and a = b²
b = -6
a = b² = 36
Answer:
The standard error of the mean is 4.5.
Step-by-step explanation:
As we don't know the standard deviation of the population, we can estimate the standard error of the mean from the standard deviation of the sample as:

The sample is [30mins, 40 mins, 60 mins, 80 mins, 20 mins, 85 mins]. The size of the sample is n=6.
The mean of the sample is:

The standard deviation of the sample is calculated as:

Then, we can calculate the standard error of the mean as:

Answer:
D
Step-by-step explanation:
ABCD is the same as JKML
M=D