Answer:
The required expression is [tex]x= \frac{M}{(1 - 0.8)}[/tex] or [tex]x=5M[/tex]
Step-by-step explanation:
Consider provided information.
After reading 80% of her emails in her inbox, Danette still has M unread emails
Now we need to determine the expression, that could represents the number of emails Danette had in her inbox before started reading.
Let x be the number of emails before reading.
She reads 80% of x
80% can be written as 0.08.
Therefore, [tex]0.80x[/tex] is the number of mails she read.
Thus, the unread e-mails are
[tex]x - 0.8x = M[/tex]
Now we factor out x
[tex]x(1 - 0.8) = M[/tex]
[tex]x=\frac{M}{(1 - 0.8)}[/tex]
[tex]x=\frac{M}{0.2}[/tex]
[tex]x=5M[/tex]
Hence, the required expression is [tex]x= \frac{M}{(1 - 0.8)}[/tex] or [tex]x=5M[/tex]
