Add 70/80 and 72/90
70/80 + 72/90 is 67/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
70/80 = 70 × 9/80 × 9 = 630/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
72/90 = 72 × 8/90 × 8 = 576/720 - Add the two like fractions:
630/720 + 576/720 = 630 + 576/720 = 1206/720 - 1206/720 simplified gives 67/40
- So, 70/80 + 72/90 = 67/40
In mixed form: 127/40
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