Add 42/45 and 7/20
42/45 + 7/20 is 77/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
42/45 = 42 × 4/45 × 4 = 168/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
7/20 = 7 × 9/20 × 9 = 63/180 - Add the two like fractions:
168/180 + 63/180 = 168 + 63/180 = 231/180 - 231/180 simplified gives 77/60
- So, 42/45 + 7/20 = 77/60
In mixed form: 117/60
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