percent means parts out of 100
so 70%=70/100
'of' means multiply
we can do
[tex]\frac{x}{70}=\frac{70}{100}[/tex]
that's the prooprtion
solving
[tex]\frac{x}{70}=\frac{70}{100}[/tex]
[tex]\frac{x}{70}=\frac{7}{10}[/tex]
times both sides by 70
[tex]x=\frac{490}{10}[/tex]
[tex]x=49[/tex]
the number is 49