num = (8/10) ^ -5 = (10/8 ) ^ 5
den = (4/10) ^ -5 = ( 10/4 ) ^ 5
so, num/den= (10/8) ^ 5 * (4/10) ^5
= 10/(2^5)
= 5/64
Keep getting the wrong answer!!!! Again what do you think?
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keerthivivek
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N => (8 / 10)^-5 ==> (10 / 8)^5
D => (4 / 10)^-4 ==> (10 / 4)^4
Then you can write ==> [ 10^5 / 8^5 ] * [ 4^4 / 10^4 ] ==> 10^4 cancel out in both fractions,
leaving you with [10 * (2^2)^4 ] / [ (2^3)^5 ] = [ 10 * 2^8 ] / [ 2^15 ]
here you can cancel out 2^8 from both N & D that leaves 10 / 2^7 = 10 / 128 = 5 / 64
Perhaps there are some other quicker ways or tricks to deal with this kinda problems....
Hope this helps!
keerthivivek;
You have a typo in the denominator, it is power of [-4]
D => (4 / 10)^-4 ==> (10 / 4)^4
Then you can write ==> [ 10^5 / 8^5 ] * [ 4^4 / 10^4 ] ==> 10^4 cancel out in both fractions,
leaving you with [10 * (2^2)^4 ] / [ (2^3)^5 ] = [ 10 * 2^8 ] / [ 2^15 ]
here you can cancel out 2^8 from both N & D that leaves 10 / 2^7 = 10 / 128 = 5 / 64
Perhaps there are some other quicker ways or tricks to deal with this kinda problems....
Hope this helps!
keerthivivek;
You have a typo in the denominator, it is power of [-4]
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moneyman
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Try this ..
By properties, n^-1=1/n^1 so
(8/10)^-5=(8^-5)/(10^-5)=(1/8^5)/(1/10^5)=(10^5/8^5)
The same way (4/10)-4=(10^4/4^4)
Therefore, (8/10)^-5/(4/10^-4)=(10^5/8^5)/(10^4/4^4)
which will be =(10^5/8^5)*(4^4/10^4) (by the rule of division)
by cross multiplying we get, (10/8^5)*(4^4)=(10/2^15)*(2^8)
which will be equal to 10/2^7 = 10/128=5/64
Hope it helps!!
By properties, n^-1=1/n^1 so
(8/10)^-5=(8^-5)/(10^-5)=(1/8^5)/(1/10^5)=(10^5/8^5)
The same way (4/10)-4=(10^4/4^4)
Therefore, (8/10)^-5/(4/10^-4)=(10^5/8^5)/(10^4/4^4)
which will be =(10^5/8^5)*(4^4/10^4) (by the rule of division)
by cross multiplying we get, (10/8^5)*(4^4)=(10/2^15)*(2^8)
which will be equal to 10/2^7 = 10/128=5/64
Hope it helps!!
Maxx
