1.)
460. 100%
74. X
X= 100•74/460
X=16.09%
2.)
175 100%
172. X
X=172•100/175
X=98.28%
(x^4 - 9)(x^3 + 9)
This is a binomial * binomial. Use the FOIL method for multiplying.
First, outer, inner, last.
x^4 * x^3 = x^7
x°^4 * 9 = 9x^4
-9 * x^3 = -9 x^3
-9 * 9 = -81
Putting it back together.
x^7 +9x^4 -9x^3 - 81
Just multiply 20 by both sides.
n = 20(6/8)
Multiply that out and that is your answer :)
