Simple math help

[GomerPyle]

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I am usually very good at math but having a brain fart today. How would you guys go about answering this square root of fraction problem.

Solve for v.

v = SquareRoot((1+22.4x10^8)/1000)

The way I did it: I just got rid of the 1 because it is so much smaller than 22.4x10^8 and then got SquareRoot((22.4x10^8)/1000). So now you have SquareRoot(22.4x10^5). Square root of is 1/2 of the exponent so it would be 22.4x10^5/2. Now what do you do with the exponent that is a fraction?

The answer is 1.4x10^3. What the hell am I not seeing??

Thanks guys.

 

[QrtrLifeCrisis]

I am usually very good at math but having a brain fart today. How would you guys go about answering this square root of fraction problem.

Solve for v.

v = SquareRoot((1+22.4x10^8)/1000)

The way I did it: I just got rid of the 1 because it is so much smaller than 22.4x10^8 and then got SquareRoot((22.4x10^8)/1000). So now you have SquareRoot(22.4x10^5). Square root of is 1/2 of the exponent so it would be 22.4x10^5/2. Now what do you do with the exponent that is a fraction?

The answer is 1.4x10^3. What the hell am I not seeing??

Thanks guys.

If you see something like this on test day, I would probably get as close as possible to an answer via rounding and then look at the answers to see which is closest. That said...here's what I would have done.

When you get to SquareRoot(22.4x10^5)...it is the same as SquareRoot(224x10^4). Pull out the 10^4 as 10^2. The SquareRoot(224=225) = 15. The answer you get is 15 *10^2, which is really close to 1.4 *10^3.

 

[msj6403]

If you see something like this on test day, I would probably get as close as possible to an answer via rounding and then look at the answers to see which is closest. That said...here's what I would have done.

When you get to SquareRoot(22.4x10^5)...it is the same as SquareRoot(224x10^4). Pull out the 10^4 as 10^2. The SquareRoot(224=225) = 15. The answer you get is 15 *10^2, which is really close to 1.4 *10^3.

Very similar, but I would have done a different way. Try them and see which one is more intuitive to you, OP. The important key here is that you want to make 10^5 to be "even" like 10^4 or 10^6, so that after square root, you get 10^2 or 10^3 (just divide the powers by 2 since square root is the same as ^0.5)

Square root(22.4x10^5) -> decide which: square root (2.24x10^6) or (224x10^4) -> if you don't know the square root of 225 like the poster up, try the other way, like square root of 2 is about 1.4 something -> so square root (2 something x 10^6) = 1.4 something x 10^3.

I hope it helps!

 

[GomerPyle]

I can't believe I didn't see that. Thanks guys.