Answer:
Year 2031
Step-by-step explanation:
We need to use the formula for compound growth here, that is:
[tex]F=P(1+r)^t[/tex]
Where
F is future amount (1 billion)
P is present amount (1.2 million)
r is rate of growth (21% or 0.21)
t is the time (we need to find this)
Putting in the values we have:
[tex]F=P(1+r)^t\\1,000,000,000=1,200,000(1+0.21)^t\\833.33=(1.21)^t\\Ln(833.33)=Ln((1.21)^t)\\Ln(833.33)=t*Ln(1.21)\\t=\frac{Ln(833.33)}{Ln(1.21)}\\t=35.28[/tex]
So after about 35.28 years, the number of phones will cross 1 billion, so we take the next year, so after 36 years.
From 1995 to 36 years would be the year 2031
