850 is 100%, so 532 is x% — this is a ratio:
850:100% = 532:x% — inverse multiplication (inner with inner, outer with outer)
x% * 850 = 100% * 532 — divide the whole eqtn with 850 to isolate x%
x% = (100% * 532) / 850
x% = 53200% / 850
x% = 62.5% (roughly)