We have originally sent 3571 emails.
Solution:
Let x be the number of emails originally sent.
We know that, [tex]7 \%-\frac{7}{100}=0.07[/tex]
Therefore, [tex]x \times 0.07=250[/tex]
On solving for x , divide by 0.07 both sides
[tex]\Rightarrow\frac{x \times0.07}{0.07}=\frac{250}{0.07}[/tex]
[tex]\Rightarrow x\times0.07=250[/tex]
[tex]\Rightarrow x=\frac{250}{0.07}=3571.428\approx3571[/tex]
Therefore, number of mails sent 3571.