A city that had 40,000 trees started losing them at a rate of 10 percent per year because of urbanization.
1 answer:
Answer:
t = 13.1576 years
Step-by-step explanation:
The situation can be modeled as
P = Po.(1-r)^t
Where
t is the years transcurred
Po is the initial amount
r is the rate of change
Po = 40000
r = 10% equivalent to 0.1
Now
A quarter of the original amount
(1/4)*Po = Po.(1-r)^t
(1/4) = (0.9)^t
t = 13.1576
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Answer:
Number of sent mail = 36
Number of received mail = 75
Step-by-step explanation:
Let,
x be the number of mails sent
y be the number of mails received
According to given statement;
x + y = 111 Eqn 1
y = 2x + 3 Eqn 2
Putting value of y from Eqn 2 in Eqn 1
x + 2x + 3 = 111
3x = 111 - 3
3x = 108
Dividing both sides by 3
Putting x = 36 in Eqn 2
y = 2(36) + 3
y = 72 + 3 = 75
Hence,
Number of sent mail = 36
Number of received mail = 75