A certain whole number has the property that appending a digit $5$ has the effect of adding $3074$ . What is the original number?

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Answer 1 · 2017-03-22T00:06:31

$341$

If the original number is $n$ , then the number formed by tacking a $5$ on the end is $10n+5$

So:

$10n+5 = n+3074$

Subtract $n+5$ from both sides to get:

$9n = 3069$

Divide both sides by $9$ to get:

$n = 341$

A certain whole number has the property that appending a digit 55 has the effect of adding 30743074. What is the original number?