Answer:
you can cross multiply or u can 7/20 to get the answer that 7 is 35% of 20
For each <em>x</em> in the interval 0 ≤ <em>x</em> ≤ 5, the shell at that point has
• radius = 5 - <em>x</em>, which is the distance from <em>x</em> to <em>x</em> = 5
• height = <em>x</em> ² + 2
• thickness = d<em>x</em>
and hence contributes a volume of 2<em>π</em> (5 - <em>x</em>) (<em>x</em> ² + 2) d<em>x</em>.
Taking infinitely many of these shells and summing their volumes (i.e. integrating) gives the volume of the region:

For this case, the first thing we should do is use the following equation:
f (x) = 200 (1.03) ^ x
We substitute f (x) = 300:
300 = 200 (1.03) ^ x
We clear the value of x:
log1.03 (300/200) = log1.03 ((1.03) ^ x)
x = log1.03 (300/200)
x = 13.72
Answer:
the population will first reach 300 in about 13.72 years.
The bag of cat food will last for 24 days.
(6 divided by .25 is 24.)