Question

Tìm x biết:

a) 3737:(14-x+100)=37

b) (x+1)+(x+2)+(x+3)+(x+4)+(x+5)=355

Answer 1

a) => 14 - x + 100 = 101

=> 14 - x = 1

=> x = 13

b) => 5x + (1 + 2 + 3 + 4 + 5) = 355

=> 5x + 15 = 355

=> 5x = 340

=> x = 68

Answer 2

\(b.\left(x+1\right)+\left(x+2\right)+\left(x+3\right)+\left(x+4\right)+\left(x+5\right)=355\)

\(\left(x.5\right)+\left(1+2+3+4+5\right)=355\)

\(\left(x.5\right)+15=355\)

\(x.5=355-15\)

\(x.5=340\)

\(x=340:5\)

\(x=68\)

Answer 3

a) \(3737:\left(14-x+100\right)=37\)

\(\Rightarrow14-x+100=3737:37\)

\(\Rightarrow14-x+100=101\)

\(\Rightarrow14-x=101-100\)

\(\Rightarrow14-x=1\)

\(\Rightarrow x=14-1\)

\(\Rightarrow x=13\)

Vậy \(x=13\)

b) \(\left(x+1\right)+\left(x+2\right)+\left(x+3\right)+\left(x+4\right)+\left(x+5\right)=355\)

\(\Rightarrow\left(x+x+x+x+x\right)+\left(1+2+3+4+5\right)=355\)

\(\Rightarrow5x+15=355\)

\(\Rightarrow5x=355-15\)

\(\Rightarrow5x=340\)

\(\Rightarrow x=340:5\)

\(\Rightarrow x=68\)

Vậy \(x=68\)