How do you convert #7.121 x 10^9# into expanded notation?

1 Answer
Aug 1, 2018

Answer:

7,121,000,000

Explanation:

To expand out #7.121 * 10^9#, we can imagine moving the decimal place 9 times to the right and filling in any spaces with zeros:

#7.1210000000# (0 times)
#71.210000000# (1 time)
#712.10000000# (2 times)
#7121.0000000# (3 times)
#71210.000000# (4 times)
#712100.00000# (5 times)
#7121000.0000# (6 times)
#71210000.000# (7 times)
#712100000.00# (8 times)
#7121000000.0# (9 times)

To check, we know that #10^9# is a billion, so we expect the number to be in the billions and checking just by how many commas we add supports that.