40 is <span> a multiple of 4 that is greater than 30 but less than 100.</span>
Answer:
24 units ²
Step-by-step explanation:
In this problem, we are given the circumference of a triangle (after finding the perimeter) and want to find the area of a circle with that circumference. Since the area of a circle is a function based on its radius, we can use the circumference to find the radius to find the area.
First, we can figure out the perimeter of the triangle, which is equal to the sum of its sides. The perimeter is 6+4+7.21 = 17.21 units.
Next, the circumference of a circle is equal to π * diameter = π * 2 * radius. Using 3.14 for π and r for radius, we get
3.14 * 2 * r = 17.21
6.28 * r = 17.21
divide both sides by 6.28 to isolate r
r ≈ 2.74
Furthermore, to find the area from the radius, we can use
area = πr². Plugging 2.74 in for r, we get
2.74² * 3.14 = area
≈23.6, rounding up to 24 units ²
The bacteria would double every 20 minutes, so before then is when the bacteria is still in its singular form before it doubles.
Approximately 34% of a normal distribution is within 1 standard deviation above the mean. Your probability is about 100% - (50% +34%) = 16%.
_____
This is a number most statistics students are asked to memorize.
