The Turbocharger Bible

How about some help with the some of the math.

T1 = 75
P1 = 14.7
P2 = 24.7

The formula will now look like this:
T2 = 535 (24.7 ÷ 14.7)0.283 = 620 °R
You then need to subtract 460 to get °F, so simply do this:
620 - 460 = 160 °F Ideal Outlet Temperature
This is a temperature rise of 85 °F

THIS-> T2 = 535 (24.7 ÷ 14.7)0.283 = 620 °R
Is what I'm confused about. aka the 0.283
Thanks