Add 30/40 and 90/21
1st number: 30/40, 2nd number: 4 6/21
30/40 + 90/21 is 141/28.
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,
90/21 = 90 × 40/21 × 40 = 3600/840 - Add the two like fractions:
630/840 + 3600/840 = 630 + 3600/840 = 4230/840 - 4230/840 simplified gives 141/28
- So, 30/40 + 90/21 = 141/28
In mixed form: 51/28
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