Add 30/40 and 20/21
30/40 + 20/21 is 143/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
30/40 = 30 × 21/40 × 21 = 630/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
20/21 = 20 × 40/21 × 40 = 800/840 - Add the two like fractions:
630/840 + 800/840 = 630 + 800/840 = 1430/840 - 1430/840 simplified gives 143/84
- So, 30/40 + 20/21 = 143/84
In mixed form: 159/84
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