(1)/(21)+(1)/(7) - addition of fractions

Solution for the given fractions

• 1/21 + 1/7 = ?
• The common denominator of the two fractions is: 21
• 1/21 = (1*1)/(1*21) = 1/21
• 1/7 = (1*3)/(3*7) = 3/21
• Fractions adjusted to a common denominator
• 1/21 + 1/7 = 1/21 + 3/21
• (1+3)/21 = 4/21

Solution for the given fractions

$ \frac{1}{21 }+\frac{ 1}{7 }=? $

The common denominator of the two fractions is: 21

$ \frac{1}{21 }= \frac{(1*1)}{(1*21)} =\frac{ 1}{21} $

$ \frac{1}{7 }= \frac{(1*3)}{(3*7)} =\frac{ 3}{21} $

Fractions adjusted to a common denominator

$ \frac{1}{21 }+\frac{ 1}{7 }=\frac{ 1}{21 }+\frac{ 3}{21} $

$ \frac{(1+3)}{21 }=\frac{ 4}{21} $

$ $

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