The percentage could vary depending on the bell curve diagram your professor uses. I was taught that anything more than 3 standard deviations is 0.15%. So, only about 0.15% of blue whales eat more than 7,550lbs of fish.
Isolate the p terms on one side and the constants on the other side. Subtract 5p from both sides: 10 = p + 22. Next, subtract 22 from both sides, obtaining