I GIVE BRAINLILSTE ///////////////////////....
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[tex] {\bf \red {\huge{answer : }}}[/tex]
The dogs weight increased from 64 pounds to 80 pounds.
80 - 64 = 16
so , the dog's weight increased more 16 pounds.
[tex] \pink {\sf{hence , \frac{16}{80} \times 100 }}[/tex]
[tex] \red{= \frac{16}{8 \cancel{0}} \times 10 \cancel{0 } }[/tex]
[tex]\purple{= \frac{ \cancel{16}}{ \cancel{8 }} \times 10 }[/tex]
[tex]\blue{= \frac{ 2}{ 1} \times 10 }[/tex]
[tex] \green{2 \times 10 = 20\%}[/tex]
Therefore , the dog's weight increased by 20%