Scientific notation is a way of writing very large or very small numbers. A number is written in scientific notation when a number between 1 and 10 is multiplied by a power of 10. For example, 650,000,000 can be written in scientific notation as 6.5 ✕ 108

670,000,000 + 700,000,000 = 1,370,000,000 = 1.37 ✕ 109