She spent 10 minutes. 25% x 40 = 10.
Answer:
The mean weight of the cats is 11.42 (rounded)
Step-by-step explanation:
To find the mean, you add up all the weights (12, 12, 9, 9, 11, 11, 16) and then divided the sum (80) of the weights by the number of cats (7)
12+12+9+9+11+11+16= 80
80 ÷ 7= 11.42857143 (I rounded my answer to 11.42)
I hope this was helpful. Have a wonderfull rest of your day!
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)
Answer:
the answer to your question is 0.4375
20 and 45 have number 5 in common
