Find the product of 0.0409 and 0.0021 leaving your answer in the standard form
A
8.6 x 10-6
B
8.6 x 105
C
8.6 x 10-4
D
8.6 x 10-5
Verified Correct Answer: D.
Step-by-Step Mathematical Solution
0.0409 x 0.0021 = 409 x 10\(^{-4}\) x 21 x 10\(^{-4}\)
= 409 x 21 x 10\(^{-4 * -4}\)
= 8589 x 10\(^{-8}\)
= 8.589 x 10\(^{3}\) x 10\(^{-8}\)
= 8.6 x 10\(^{3-8}\)
= 8.6 x 10\(^{-5}\)
Source: WAEC / JAMB / NECO Classroom Archive (Record #36325)