Add 21/49 and 28/40
21/49 + 28/40 is 79/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 40 is 1960
Next, find the equivalent fraction of both fractional numbers with denominator 1960 - For the 1st fraction, since 49 × 40 = 1960,
21/49 = 21 × 40/49 × 40 = 840/1960 - Likewise, for the 2nd fraction, since 40 × 49 = 1960,
28/40 = 28 × 49/40 × 49 = 1372/1960 - Add the two like fractions:
840/1960 + 1372/1960 = 840 + 1372/1960 = 2212/1960 - 2212/1960 simplified gives 79/70
- So, 21/49 + 28/40 = 79/70
In mixed form: 19/70
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