Simple math question

[queenoftheclouds]

Advertisement - Members don't see this ad

Hi all, I'm stuck on the calculations of a simple math problem. EK and wolfram alpha both have the same answer, I just don't get why it's correct.

The solution states that:
4(5.4*10^-3)^3 is about(=) 20*10^-9

However, it is to my understanding that the 5.4 should be cubed as well.. Can anyone clarify??

 

[ElectricNoogie]

Hi all, I'm stuck on the calculations of a simple math problem. EK and wolfram alpha both have the same answer, I just don't get why it's correct.

The solution states that:
4(5.4*10^-3)^3 is about(=) 20*10^-9

However, it is to my understanding that the 5.4 should be cubed as well.. Can anyone clarify??

You are correct, everything in the parentheses should be cubed. Perhaps you input it into WA incorrectly? I input the calculation and got the correct answer:

4(5.4*10^-3)^3 = 4(5.4)^3 x 10^-9 = 629 x 10^-9 = 6.3 x 10^-7

As for EK I would check to see if the mistake is on their end. They have their errata HERE