Answer
45, 225, and 145
Work Step by Step
We set the first number equal to $x$.
We are given that a second number is 5 times the first number. Therefore, the second number can be represented by $5x$.
A third number is 100 more than the first number, so the third number can be represented by $x+100$.
The sum of the three numbers is 415, so $x+5x+(x+100)=415$.
Group like terms on the left side.
$7x+100=415$
Subtract 100 from both sides.
$7x=315$
Divide both sides by 7.
$x=45$
Therefore, number one is $45$, number 2 is $5\times45=225$, and number 3 is $45+100=145$