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.
we know that 60% of x is 120. we can rewrite this to .6x = 120, to get x we divide both sides by .6, so x = 200. now 120 + 30 = 150. then we divide 150 out of 200 which is .75 it 75%
