Final answer:
To subtract 2.5 x 10^8 from 4.7 x 10^8, subtract the coefficients and keep the same exponent.
Step-by-step explanation:
To subtract 2.5 x 108 from 4.7 x 108, we subtract the coefficients (4.7 - 2.5) and keep the same exponent (8).
The answer would be 2.2 x 108.