Answer:
116 cm²
Step-by-step explanation:
The area of a circle = πr² ← r is the radius
shaded area = external area - internal area
= π × 6.5² - π × 2.3²
= π( 42.25 - 5.29)
= π × 36.96 ≈ 116 cm²
Answer:
C
Step-by-step explanation:
Since the difference between 0 and -10 is 10, this means that the difference between the diving board and the pool also has to be 10. Therefore, the diving board is 10 feet above the water since 0+10 is 10.
Answer:
(1,3) should be the answer due to the fact that both lines intersect at that point.
Step-by-step explanation:
Answer:
95% confidence interval for the difference between the average mass of eggs in small and large nest is between a lower limit of 0.81 and an upper limit of 2.39.
Step-by-step explanation:
Confidence interval is given by mean +/- margin of error (E)
Eggs from small nest
Sample size (n1) = 60
Mean = 37.2
Sample variance = 24.7
Eggs from large nest
Sample size (n2) = 159
Mean = 35.6
Sample variance = 39
Pooled variance = [(60-1)24.7 + (159-1)39] ÷ (60+159-2) = 7619.3 ÷ 217 = 35.11
Standard deviation = sqrt(pooled variance) = sqrt(35.11) = 5.93
Difference in mean = 37.2 - 35.6 = 1.6
Degree of freedom = n1+n2 - 2 = 60+159-2 = 217
Confidence level = 95%
Critical value (t) corresponding to 217 degrees of freedom and 95% confidence level is 1.97132
E = t×sd/√(n1+n2) = 1.97132×5.93/√219 = 0.79
Lower limit = mean - E = 1.6 - 0.79 = 0.81
Upper limit = mean + E = 1.6 + 0.79 = 2.39
95% confidence interval for the difference in average mass is (0.81, 2.39)
