Answer:
Approximately
n = 21 years
Step-by-step explanation:
Original height of the tree = 4 1/2 feet
Final height of the tree = 40 feet
Common difference = 1 3/4 feet per year
The data shows the question is an arithmetic progression
Tn = a + (n-1) d
Tn = 40
a = 4 1/2
d = 1 3/4
n = ?
40 = 4 1/2 + ( n - 1) 1 3/4
40 = 9/2 + (n - 1) 7/4
40 = 9/2 + 7/4n - 7/4
40 = 18-7/4 + 7/4n
40 = 11/4 + 7/4n
40 - 11/4 = 7/4n
160-11/4 = 7/4n
149/4 = 7/4n
Divide both sides by 7/4
n = 149/4 ÷ 7/4
= 149/4× 4/7
= 149/7
n = 21.29 years
Answer: 50.9091 percent
