\(\left(x+1\right)+\left(x+3\right)+...+\left(x+99\right)\text{=}4900\)
\(x+1+x+3+...+x+99\text{=}4900\)
\(49x+4900\text{=}4900\)
\(49x\text{=}0\)
\(x\text{=}0\)
\(\left(x+1\right)+\left(x+3\right)+...+\left(x+99\right)=4900\)
\(\Rightarrow\left(x+x+...+x\right)+\left(1+3+...+99\right)=4900\)
\(\Rightarrow50x+2500=4900\)
\(\Rightarrow50x=2400\)
\(\Rightarrow x=48\)
Vậy x = 48.