Add 15/21 and 30/40
15/21 + 30/40 is 41/28.
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,
15/21 = 15 × 40/21 × 40 = 600/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
30/40 = 30 × 21/40 × 21 = 630/840 - Add the two like fractions:
600/840 + 630/840 = 600 + 630/840 = 1230/840 - 1230/840 simplified gives 41/28
- So, 15/21 + 30/40 = 41/28
In mixed form: 113/28
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