Bob draws an artwork measuring 2.25 inches by 2 inches. He makes a copy of the artwork, enlarging it so that its dimensions are now 3.15 inches by 2.8 inches. What scale factor did he use to create the copy of the original artwork? Write your answer as a decimal.
To find the scale factor, we can divide the new dimensions by the original dimensions.
For the width, we have 3.15 / 2.25 = 1.4.
For the height, we have 2.8 / 2 = 1.4.
The scale factor is the same for both dimensions, so we can say that Bob used a scale factor of 1.4 to create the copy of the original artwork.