Add 90/21 and 70/40
1st number: 4 6/21, 2nd number: 1 30/40
90/21 + 70/40 is 169/28.
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,
90/21 = 90 × 40/21 × 40 = 3600/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
70/40 = 70 × 21/40 × 21 = 1470/840 - Add the two like fractions:
3600/840 + 1470/840 = 3600 + 1470/840 = 5070/840 - 5070/840 simplified gives 169/28
- So, 90/21 + 70/40 = 169/28
In mixed form: 61/28
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