adding fractions with unlike denominators 1/3 + - 2/7
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Answer:
1/21
Step-by-step explanation:
Changing operations to eliminate negative numerators the equation becomes
=1/3−2/7
With unlike denominators find the Least Common Denominator (LCD)
LCD = 21
Multiplying numerators and denominators to get the LCD in all fraction denominators
=1×7/3×7 −2×3 /7×3
Then rewriting the equation with the equivalent fractions
=7/21−6/21
With like denominators we can operate on just the numerators
=7−6/21
=1/21