The centers for medicare and medicaid projects that consumers will spend more than $4×1012 on health care by 2017. write 4×1012 in decimal notation.

The answer is 4'000,000'000,000

Step-by-step explanation:

In large numbers, where the exponent of the ten is positive, we have to move the comma or dot to the right as many positions as the exponent that has the ten mark. If we have no more places to move the comma but we still have positions to move, then we will have to add zeros for each position we have left.  In this case, the exponent of ten is 12, so I have to move the comma or dot 12 positions to the right. Therefore the answer is:

Consumers will spend more than 4'000,000'000,000 on health care by 2017.