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ruchisharma
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Question
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Source: Beat The GMAT — Data Sufficiency |
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ketandoshi
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crackinggmat
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i think it should be B ONLY...
BECAUSE TO MAKE 8X AN INTEGER X COULD BE 1/2 ,1/4 ,3/4 , 1/8 ALL HAVE A NON ZERO TENTH DIGIT IN DECIMAL REPRESENTATION...
BUT IN a 16 X CAN BE AN INTEGER IF X= 1/2 , 3/4 ,1/4 ,1/8 , 1/16 ...ALL OTHER BUT 1/16 HAVE A NON ZERO TENTH DIGIT IN THE DECIMAL REPRESENTATION....
I HOPE I M RIGHT BUT IF ANYTHING IS WRONG LET ME KNOW,.....
BECAUSE TO MAKE 8X AN INTEGER X COULD BE 1/2 ,1/4 ,3/4 , 1/8 ALL HAVE A NON ZERO TENTH DIGIT IN DECIMAL REPRESENTATION...
BUT IN a 16 X CAN BE AN INTEGER IF X= 1/2 , 3/4 ,1/4 ,1/8 , 1/16 ...ALL OTHER BUT 1/16 HAVE A NON ZERO TENTH DIGIT IN THE DECIMAL REPRESENTATION....
I HOPE I M RIGHT BUT IF ANYTHING IS WRONG LET ME KNOW,.....
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clock60
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also got B here approach is the same as above, but slightly detailed
(1) 0<x<1, and 16x=k where k is an integer
k=1, x=1/16=0,0625,here tenths digit is 0.
k=2, x=2/16=1/8=0,125 here tenths digit 1
insufficient
(1) 8x=k
k=1,x=1/8=0,125 not 0
k=2,x=1/4=0,25 not 0
k=3, x=3/8=0,375
i believe that next values for k will not give 0 as tenths digit, but how to prove it?
(1) 0<x<1, and 16x=k where k is an integer
k=1, x=1/16=0,0625,here tenths digit is 0.
k=2, x=2/16=1/8=0,125 here tenths digit 1
insufficient
(1) 8x=k
k=1,x=1/8=0,125 not 0
k=2,x=1/4=0,25 not 0
k=3, x=3/8=0,375
i believe that next values for k will not give 0 as tenths digit, but how to prove it?












