(9*10^4)(8*10^6) Write the results in scientific notation

Question

7.2*10^25
1.7*10^11
7.2*10^11
1.7*10^25

my answer 1.7*10^11

Answer 1

9 times 10^4 multiplied
8 times 10^6

multiply 9 times 8 = 72

with exponents you keep the base and add the exponents.

72 times 10^10

sci notation calls for one decimal place only

7.2 times 10^11

You have your exponent right, but didn't multiply the coefficients.