Add 21/42 and 30/40
21/42 + 30/40 is 5/4.
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,
21/42 = 21 × 20/42 × 20 = 420/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
30/40 = 30 × 21/40 × 21 = 630/840 - Add the two like fractions:
420/840 + 630/840 = 420 + 630/840 = 1050/840 - 1050/840 simplified gives 5/4
- So, 21/42 + 30/40 = 5/4
In mixed form: 11/4
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