First, we have to find the z scores of $4 and $9.50.
Z₁ = ($4 - $6.50)/$2.25 = -1.11
Z₂ = ($9.50 - $6.50)/$2.25 = 1.33
Then, using a z score table, we find the probability of 1.33 and -1.11, and subtract them to determine the probability in between.
0.9082 - 0.1335 = 0.7747 or 77.47%.
Answer:
( x - 2 ) ( x + 2 ) ( x² + 4 ) - ( x² - 2 ) ( x² + 3 )
(x²– 4) (x²+4) – (x⁴ + x² – 6)
( x⁴ – 16 ) – ( x⁴ + x² – 6 )
( x⁴ – 16 ) + ( – x⁴ – x² + 6 )
– x² – 10
I hope I helped you^_^
