Add 90/84 and 21/80
1st number: 1 6/84, 2nd number: 21/80
90/84 + 21/80 is 747/560.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 84 × 20 = 1680,
90/84 = 90 × 20/84 × 20 = 1800/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
21/80 = 21 × 21/80 × 21 = 441/1680 - Add the two like fractions:
1800/1680 + 441/1680 = 1800 + 441/1680 = 2241/1680 - 2241/1680 simplified gives 747/560
- So, 90/84 + 21/80 = 747/560
In mixed form: 1187/560
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