Question

Tìm x biết

\((1+X)+\left(2+X\right)+\left(3+X\right)+...+\left(10+X\right)=75\)\(X\div[\left(1800+600\right)\div30]=560\div\left(315-35\right)\)

Answer 1

(1 + x) + (2 + x) + (3 + x) + ... + (10 + x) = 75

=> (1 + 2 + 3 + ... + 10) + (x + x + x + ... + x) = 75

=> 55 + 10x = 75

=> 10x = 20

=> x = 2

vậy_

x : [(1800 + 600) : 30] = 560 : (315 - 35)

=> x : [2400 : 30] = 560 : 280

=> x : 80 = 2

=> x = 160

vậy_

Answer 2

Câu 1: x = 2

Câu 2: x = 280/3

Answer 3

\(\left(x+1\right)+\left(x+2\right)+...+\left(x+10\right)=75\)

\(10x+45=75\)

\(10x=75-45=30\)

\(x=30:10=3\)