Answer:
24
Explanation:
the question translates to asking how many times does 7/8 fit in 21, so 21 divided by 7/8.
when we divide by a fraction, we can multiply by it's inverse, so 21 divided by 7/8, is 21 multiplied by 8/7. so:
21×8/7 = (21×8)/7 = (21/7)×8 = 3×8 = 24