`s/(2.5) + s/(2.12) +7/15 = s/5` tìm s

2 bình luận về “`s/(2.5) + s/(2.12) +7/15 = s/5` tìm s”

1. s/(2.5)+s/(2.12)+7/15=s/5

   =>s/10+s/24=s/5-7/15

   =>(12s)/120+(5s)/120=(3s)/15-7/15

   =>(17s)/120=(3s-7)/15

   =>(17s)/120=(8(3s-7))/120

   =>17s=8(3s-7)

   =>17s=24s-56

   =>24s-17s=56

   =>7s=56

   =>s=8

   Trả lời
2. Giải đáp:

    \frac{s}{2.5}+\frac{s}{2.12}+\frac{7}{15}=\frac{s}{5}

   => \frac{s}{2}.(\frac{1}{5}+\frac{1}{12})+\frac{7}{15}=\frac{s}{5}

   => \frac{s}{2}.\frac{17}{60}+\frac{7}{15}=\frac{s}{5}

   => \frac{17s}{120}+\frac{56}{120}=\frac{24s}{120}

   => 17s+56=24s

   => 17s-24s=-56

   => -7s=-56

   => s=8

   Vậy s=8

   Trả lời