The normal rule to remember is 68-95-99.7, i.e. plus or minus three sigma corresponds to 99.7% of the probability. That leaves 0.3% in the two tails, or 0.15% in the tail above 3 sigma.
Answer: 0.15%
First you need to distribute the exponent into the terms for the first parenthesis.
(-3x²y³)³ = (-3)³ * (x²)³ * (y³)³
= -27 *x⁶ *y⁹
= -27x⁶y⁹
Then you multiply -27x⁶y⁹ by x²y.
You just need to add the exponents of x and y:
-27x⁶⁺²y⁹⁺¹
= -27x⁸y¹⁰
I THINK the answer is compatible numbers.............. but I'm pretty sure it is compatible numbers