(10^8 - 10^2) / (10^7 - 10 ^3) is closest to 10?
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(10^8-10^2)/(10^7-10^3)
take out 10^2 and 10^3 common from the num and den
[10^2(10^6-1)]/[10^3(10^4-1)]
Simplify the fraction by dividing 10^2/10^3 you get
(10^6-1)/[10(10^4-1)]
Now 10^6-1 is approx = 10^6
and 10^4-1 is approx = 10^4
So we get
(10^6)/[10(10^4)]
=(10^6)/(10^5)
=10
take out 10^2 and 10^3 common from the num and den
[10^2(10^6-1)]/[10^3(10^4-1)]
Simplify the fraction by dividing 10^2/10^3 you get
(10^6-1)/[10(10^4-1)]
Now 10^6-1 is approx = 10^6
and 10^4-1 is approx = 10^4
So we get
(10^6)/[10(10^4)]
=(10^6)/(10^5)
=10
Thanks for the explanation. I factored out 10^2 in the numerator and 10^3 in the denominator but should have estimated/approximated!mals24 wrote:(10^8-10^2)/(10^7-10^3)
take out 10^2 and 10^3 common from the num and den
[10^2(10^6-1)]/[10^3(10^4-1)]
Simplify the fraction by dividing 10^2/10^3 you get
(10^6-1)/[10(10^4-1)]
Now 10^6-1 is approx = 10^6
and 10^4-1 is approx = 10^4
So we get
(10^6)/[10(10^4)]
=(10^6)/(10^5)
=10
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10^8 is super-super big relative to 10^2.
So 10^8 - 10^2 will be very close to 10^8.
Likewise, 10^7 - 10^3 will be very close to 10^7.
So the question becomes:
what is 10^8/10^7 close to?
Clearly, it is close to 10.
So 10^8 - 10^2 will be very close to 10^8.
Likewise, 10^7 - 10^3 will be very close to 10^7.
So the question becomes:
what is 10^8/10^7 close to?
Clearly, it is close to 10.
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Maybe the way I asked wasnt as clear,
I know 10^8 is super big comparing to 10^2. I didnt know why you just delete 10^2 but I guess even when you minus 10^2 from 10^8 it is still close to 10^8, is that why you just delete 10^2 and leave 10^8?
I know 10^8 is super big comparing to 10^2. I didnt know why you just delete 10^2 but I guess even when you minus 10^2 from 10^8 it is still close to 10^8, is that why you just delete 10^2 and leave 10^8?
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Since the question asks only for an approximate answer, yes you ignore 10^2. However, if the question asks for an exact answer, don't approximate!
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Jose had $100,000,000 and gave $100 to charity. Luis had $10,000,000 and gave $1,000 to charity. After their charitable giving, approximately how many times as much money as Luis did Jose have ?
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Take 10^2 common from Nr. & 10^3 from the Dr.--> 10^2(10^6-1)/10^3(10^4-1)
(10^6-1) approx = 10^6 and (10^4-1) approx= 10^4
so the fraction reduces to (10^6)/10(10^4)=10 & It is the answer
(10^6-1) approx = 10^6 and (10^4-1) approx= 10^4
so the fraction reduces to (10^6)/10(10^4)=10 & It is the answer