Answer:
30
Step-by-step explanation:
2/3 = x/18
2*18 = 3x
36 = 3x
x=12
so there are 12 boys
12+18=30
Answer:
\frac{79}{9} \pi
Step-by-step explanation:
With the help of theorems involving circles, assuming that arc ABC is a central angle (meaning both legs of the angle start from the centerpoint), the measure of the inscribed angle is twice that of the central angle. Thus, arc AC is equal to 2*40°= 80°.
Answer:
p -1 = 5p + 3p -8
p=1
Step-by-step explanation:
p -1 = 5p + 3p -8
Combine like terms
p-1 = 8p -8
Subtract p from each side
p-1-p = 8p-p -8
-1 = 7p -8
Add 8 to each side
-1 +8 =7p-8+8
7 = 7p
Divide by 7
7/7 = 7p/7
1 =p
Answer:
+/- 1.9983
Step-by-step explanation:
The critical values for a confidence interval for the population mean, with population standard deviation not known, are obtained from the student's t distribution.
The sample size is given as 64. The degrees of freedom will thus be;
sample size - 1 = 64 - 1 = 63
The confidence level is given as 95%. The level of significance will thus be;
100 - 95 = 5%.
The area in the right-tail will thus be 2.5%. Therefore, we looking for a t-value such that the area to its right is 2.5% and the degrees of freedom being 63. From the t-tables we have;
+/- 1.9983
