Add 21/70 and 63/64
21/70 + 63/64 is 411/320.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 64 is 2240
Next, find the equivalent fraction of both fractional numbers with denominator 2240 - For the 1st fraction, since 70 × 32 = 2240,
21/70 = 21 × 32/70 × 32 = 672/2240 - Likewise, for the 2nd fraction, since 64 × 35 = 2240,
63/64 = 63 × 35/64 × 35 = 2205/2240 - Add the two like fractions:
672/2240 + 2205/2240 = 672 + 2205/2240 = 2877/2240 - 2877/2240 simplified gives 411/320
- So, 21/70 + 63/64 = 411/320
In mixed form: 191/320
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