Answer:
25 years
Step-by-step explanation:
Solution:-
- Data for the average daily temperature on January 1 from 1900 to 1934 for city A.
- The distribution X has the following parameters:
Mean u = 24°C
standard deviation σ = 4°C
- We will first construct an interval about mean of 1 standard deviation as follows:
Interval for 1 standard deviation ( σ ):
[ u - σ , u + σ ]
[ 24 - 4 , 24 + 4 ]
[ 20 , 28 ] °C
- Now we will use the graph given to determine the number of years the temperature T lied in the above calculated range: [ 20 , 28 ].
T1 = 20 , n1 = 2 years
T2 = 21 , n2 = 3 years
T3 = 22 , n3 = 2 years
T4 = 23 , n4 = 4 years
T5 = 24 , n5 = 3 years
T6 = 25 , n6 = 3 years
T7 = 26 , n7 = 5 years
T8 = 27 , n8 = 2 years
T5 = 28 , n9 = 1 years
- The total number of years:
∑ni = n1 + n2 + n3 + n4 + n5 + n6 + n7 + n8 + n9
= 2 + 3 + 2 + 4 + 3 + 3 + 5 + 2 + 1
= 25 years