Hello, Godfather!

A tricky/sneaky/challenging problem . . .

A car dealer sold two used cars for $9999 each.

On one she made a 10% profit and the other she took a 10% loss.

What is the dollar amount of her overall loss over the two transactions?

For the first car, the selling price was $9999 including a 10% profit.

That is, $9999 equals the Cost plus 10% of the Cost.

The equation is: .C + 0.10C .= .9999 . → . 1.1C = 9999 . → . C = 9090

The car cost her $9090 and she sold it for $9999.

. . She made a profit of $909.

For the second car, the selling price was $9999 including a 10% loss.

That is, $9999 is the Cost minus 10% of the Cost.

The equation is: .C - 0.10C .= .9999 . → . 0.9C = 9999 . → . C = 11,110

The car cost her $11,100 and she sold it for $9999.

. . She had a loss of $1,110.

Therefore, her overall loss is: .$1,110 - 909 .= .$201