When the firecracker hits the ground, H(t) = 0.0 = -16t^2 + 90t + 160 Using the quadratic formula,t = (-90 +- sqrt(90^2 - 4(-16)(160))) / 2(-16)t = -1.42 ort = 7.04
The negative time is extraneous. Therefore,t = 7.04 s.
Seven Seconds is your answer!
Answer: 0.4 pounds of the trail mix is oats.
To find the answer, you can set up a proportion. We can use the percent proportion below.
part/whole = percent/100
x/2 = 20/100
To solve this you cross multiply and divide.
100x = 40
x = 0.4
If my calculations are correct , only 26 stacks of folders will only hold 7 folders evenly .. leaving 1 pile with 9 folders because 26*7= 182 & 184-182 = 2 . 7+2=9
