Add 42/21 and 75/40
1st number: 2 0/21, 2nd number: 1 35/40
42/21 + 75/40 is 31/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
42/21 = 42 × 40/21 × 40 = 1680/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
75/40 = 75 × 21/40 × 21 = 1575/840 - Add the two like fractions:
1680/840 + 1575/840 = 1680 + 1575/840 = 3255/840 - 3255/840 simplified gives 31/8
- So, 42/21 + 75/40 = 31/8
In mixed form: 37/8
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