Add 90/21 and 72/80
1st number: 4 6/21, 2nd number: 72/80
90/21 + 72/80 is 363/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
90/21 = 90 × 80/21 × 80 = 7200/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
72/80 = 72 × 21/80 × 21 = 1512/1680 - Add the two like fractions:
7200/1680 + 1512/1680 = 7200 + 1512/1680 = 8712/1680 - 8712/1680 simplified gives 363/70
- So, 90/21 + 72/80 = 363/70
In mixed form: 513/70
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