Question

1 supra 28 + 7 supra 72 + 1 supra 84=?

Answer 1

$\frac{1}{28} + \frac{7}{72} + \frac{1}{84} = \frac{18}{504} + \frac{49}{504} + \frac{6}{504} = \frac{73}{504}$

Answer 2

1/28+7/72+1/84
=[1/(7×2×2)+7/(2×3×3×2×2)+1/(2×2×2×7×2)]/504
=(18+49+6)/504
=73/504