Add 90/42 and 21/40
1st number: 2 6/42, 2nd number: 21/40
90/42 + 21/40 is 747/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
90/42 = 90 × 20/42 × 20 = 1800/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
21/40 = 21 × 21/40 × 21 = 441/840 - Add the two like fractions:
1800/840 + 441/840 = 1800 + 441/840 = 2241/840 - 2241/840 simplified gives 747/280
- So, 90/42 + 21/40 = 747/280
In mixed form: 2187/280
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