What number do you need to add to 0.015 to make it 1?

To find the number needed to add to 0.015 to make it 1, you can set up the equation 0.015 + x = 1. By subtracting 0.015 from both sides, you get x = 1 - 0.015 = 0.985. Therefore, you would need to add 0.985 to 0.015 to make it 1.