Question

The wildflowers at a national park have been decreasing in numbers. There were 1200 wildflowers in the first year that the park started tracking them. Since then, there have been one fourth as many new flowers each year. Create the sigma notation showing the infinite growth of the wildflowers and find the sum, if possible. Year New flowers 1 1200 2 300 3 75

Answer 1

Year      New flowers

1                 1200

2                 300

3                   75

There were 1200 wildflowers in the first year that the park started tracking them. Since then, there have been one fourth as many new flowers each year

Initially there are 1200 flowers and start decreasing by $\frac{1}{4}$

So first term is 1200 and common ratio is $\frac{1}{4}$.

Its a geometric sequence so summation becomes

i =1∑ ∞ 1200($\frac{1}{4})^{i-1}$

Now we find the sum

We use sum formula

$Sum = \frac{a}{1-r}$

Where a is the first term , a= 1200

r is the common ratio , r= 1/4

$Sum = \frac{1200}{1-(\frac{1}{4})}$

$Sum = \frac{1200}{\frac{3}{4}}$

Sum = 1600 wildflowers