Respuesta :

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               Hi my lil bunny!

   ❧⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯☙

[tex]\frac{3}{7}+\frac{5}{21}[/tex]

[tex]= \frac{3}{7}+\frac{5}{21}[/tex]

[tex]= \frac{9}{21}+\frac{5}{21}[/tex]

[tex]= \frac{9 + 5}{21}[/tex]

[tex]= \frac{14}{21}[/tex]

[tex]= \frac{2}{3}[/tex] (Decimal: 0.666667)

Answer : [tex]\boxed{\frac{2}{3} }[/tex] (Decimal: 0.666667)

 ❧⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯☙

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        Have a great day/night!

                   ❀*May*❀

3/7+5/21=2/3

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21

For the 1st fraction, since 21 × 1 = 21,
5
21
=
5 × 1
21 × 1
= 5/21

Likewise, for the 2nd fraction, since 7 × 3 = 21,
3
7
=
3 × 3
7 × 3
= 9/21

Add the two fractions:
5
21
+
9
21
=
5 + 9
21
= 14/21

Simplify and get 2/3