19. The formula for finding the volume of a sphere is 4/3πr^3
The problem says the radius is 9.25 cm.
Just plug in the numbers and solve:
4/3(3.14)(9.25^3)
9.25^3 = ~791.45
4/3(3.14)(791.45)
4/3 • 3.14 = ~4.19
4.19 • 791.45 = 3316.1755
It says to round to 2 decimal places so the answer to this question would be 3316.18.
That means 3316.18 is the volume of the sphere.
20. It's always best to change words into an equation.
-16 - w
w = -23
Plug in the number to the variable:
-16 - (-23)
Double negatives (a negative being subtracted) turn into a plus (positive being added).
-16 + 23 = 7
So the answer is 7.
25. Complementary angles are angles with a sum of 90º.
If angle A is 27º, just subtract that from 90º to get the measure of angle B.
90 - 27 = 63
So angle B is 63º, and the answer is A.
Since the total circumference of the circle is 60 pi cm which passes around 360˚, the length of an arc of 140˚ will be equal to 140/360 = 7/18 times the total length:
l = (7/18) * 60 pi cm = 23.3 pi cm
Answer:
Step-by-step explanation:
<u>Given inequality:</u>
Mark the point 3.2 with open dot and shade zone right to that point.
<em>See attached</em>
Answer:
2 hours
Step-by-step explanation:
The relation between time, speed, and distance is ...
time = distance/speed
For a kayak speed of k miles per hour in still water, the speed upstream is (k-2) and the speed downstream is (k+2). Over the distances given, the times are the same, so we can write ...
10/(k-2) = 14/(k+2)
Multiplying by (k+2)(k-2) gives ...
10(k+2) = 14(k -2)
10k +20 = 14k -28 . . . . . eliminate parentheses
48 = 4k . . . . . . . . . . . . . . add 28-10k
12 = k
Then the time for 28 miles downstream is ...
time = 28 / (12 +2) = 2 . . . . hours
It will take the person 2 hours to kayak 28 miles downstream.