1647. 1 hour=60 minutes. John can mow 247 square feet per minute, so he can mow 60*247=14820 square feet per hour. 1 yard=3 feet, so 1 square yard =3^2=9 square feet, so in the same duration of time, John can mow 14820/9=1647 square yards (approximately) per hour.
Step-by-step explanation:
Given:
x = 26214.47
s = 5969.25
n = 15
t = 2.046
The confidence interval is:
CI = x ± t (s / √n)
CI = 26214.47 ± 2.046 (5969.25 / √15)
CI = (23061.06, 29367.88)