So basically each of the tile sides measure one foot, since one foot = 12 inches.
We will call one of the tiles a unit.
And since the room is 14 feet by 10 feet, we can multiply the two dimensions together to see how many units fit into the room.
14 * 10 = 140
And so now we know that we need 140 tiles.
And since each tile costs $1.25, we can multiply that by 140 to get the total cost.
1.25 * 140 = $175
So it will cost Emma $175 to complete her project.