Can anyone help me solve : 5³ - 10² = ?⁵

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topsyturvy
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Joined: Fri Mar 02, 2012 10:33 am

Can anyone help me solve : 5³ - 10² = ?⁵

Post by topsyturvy »

5³ - 10² = ?⁵

steps please
hermanmunster
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Re: Can anyone help me solve : 5³ - 10² = ?⁵

Post by hermanmunster »

well I think I would turn it into normal numbers

5^3 = 125
10^2 = 100

so 125-100=25

or 5^2
doodles
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Re: Can anyone help me solve : 5³ - 10² = ?⁵

Post by doodles »

5x5x5 - 10x10

125 - 100

= 25

Ds2 tells me this is BIDMAS
Knowledge is knowing that a tomato is a fruit, wisdom is not putting it in a fruit salad !
topsyturvy
Posts: 243
Joined: Fri Mar 02, 2012 10:33 am

Re: Can anyone help me solve : 5³ - 10² = ?⁵

Post by topsyturvy »

Thanks, I did know how to solve the first part, looking for ?

but the answer has to be to the power of 5

I am looking for ? in this sum ?⁵

:roll:
Ladymuck
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Re: Can anyone help me solve : 5³ - 10² = ?⁵

Post by Ladymuck »

Has to be a typo if an 11+ question.
Proud_Dad
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Re: Can anyone help me solve : 5³ - 10² = ?⁵

Post by Proud_Dad »

I agree that its probably a typo and should read ?^2 rather than ?^5.

(If it really is ?^5, then ? = 25^(1/5) = 1.904 )
topsyturvy
Posts: 243
Joined: Fri Mar 02, 2012 10:33 am

Re: Can anyone help me solve : 5³ - 10² = ?⁵

Post by topsyturvy »

Thanks proud Dad.

This is non-calculator, can you tell me the steps you used to get to 1.904
Tinkers
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Re: Can anyone help me solve : 5³ - 10² = ?⁵

Post by Tinkers »

topsyturvy wrote:Thanks proud Dad.

This is non-calculator, can you tell me the steps you used to get to 1.904
Unless you use log tables you can't do this without a calculator I don't think. Not easily anyway. Unless you use trial and improvement, that would take for ever.

There is a way of finding out square roots without a calculator (I learnt, then forgot it many many moons ago) but I wouldn't expect any child these days to have a clue, let alone finding a 5th root.
Proud_Dad
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Re: Can anyone help me solve : 5³ - 10² = ?⁵

Post by Proud_Dad »

topsyturvy wrote:Thanks proud Dad.

This is non-calculator, can you tell me the steps you used to get to 1.904
I didn't strictly use a calculator (but I did use the calc app on my mobile to work out 25^0.2 :mrgreen: )

You can't really do it without a calculator tbh. Only way I can think of to do a rough estimate in my head is that 2^5 = 32 so the answer would be a bit less than 2.

As I and others said I think the question has a typo.
topsyturvy
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Joined: Fri Mar 02, 2012 10:33 am

Re: Can anyone help me solve : 5³ - 10² = ?⁵

Post by topsyturvy »

Thank you, much appreciated for all replies and feedback!
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