Explanation:
so, the question is
5/8 > 7/10 ?
or
7/10 > 5/8 ?
to compare fractions for real we need to bring them both to the same denominator (bottom part). then the numerators (top part) can give us all the answers precisely.
to bring a fraction to another denominator we can either split it further into subunits (like splitting halves into quarters, or 1/2 = 2/4), combine subunits (simplify the fraction) like from 2/4 to 1/2.
now, what number would designate subunits for tenths and for eighths ?
the easiest way (works always) is simply to multiply both numbers : 10×8 = 80. so, we are looking at x/80.
but we can simplify this by finding the least common multiple (LCM) of both numbers.
that is actually 40 for 10 and 8.
40 = 4×10 = 5×8
so,
5/8 = (5×5)/40 = 25/40
7/10 = (7×4)/40 = 28/40
that means
7/10 > 5/8
and Lexi ran therefore further.