Add 21/80 and 70/63
1st number: 21/80, 2nd number: 1 7/63
21/80 + 70/63 is 989/720.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 63 is 5040
Next, find the equivalent fraction of both fractional numbers with denominator 5040 - For the 1st fraction, since 80 × 63 = 5040,
21/80 = 21 × 63/80 × 63 = 1323/5040 - Likewise, for the 2nd fraction, since 63 × 80 = 5040,
70/63 = 70 × 80/63 × 80 = 5600/5040 - Add the two like fractions:
1323/5040 + 5600/5040 = 1323 + 5600/5040 = 6923/5040 - 6923/5040 simplified gives 989/720
- So, 21/80 + 70/63 = 989/720
In mixed form: 1269/720
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