4) 62.8 cm^2
5) It is quadrupled
Answer: 4x^2 - 10x - 6
Step-by-step explanation:
You can use FOIL to do this. First terms, Outer terms, Inner terms, Last terms.
(x - 3)(4x + 2)
First terms: x * 4x = 4x^2
Outer terms: x * 2 = 2x
Inner terms: -3 * 4x = -12x
Last terms: -3 * 2 = -6
Now add these together:
4x^2 + 2x - 12x - 6 = 4x^2 - 10x - 6
Let x be a random variable representing the mean number of flaws per square yard inspected
P(x > 1.8) = P(z > (1.8 - 1.7)/0.8) = P(z > 0.125) = P(z < 0.125) = 0.5497
