least distance problem-GMAT PREP
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one possible way to solve is to find LCM of 7 and 5, it must be 35
and then list all multiples of 5 and 7 between 1 and 35
for 5 it must be 5. 10. 15. 20. 25.30.35
for 7 1, 14, 21, 28, 35
the least distance 21-20=1. or 15-14=1
so desired answer 1/35
and then list all multiples of 5 and 7 between 1 and 35
for 5 it must be 5. 10. 15. 20. 25.30.35
for 7 1, 14, 21, 28, 35
the least distance 21-20=1. or 15-14=1
so desired answer 1/35
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Thanks, for maximum distance (35-1)/35 ?? correct ?clock60 wrote:one possible way to solve is to find LCM of 7 and 5, it must be 35
and then list all multiples of 5 and 7 between 1 and 35
for 5 it must be 5. 10. 15. 20. 25.30.35
for 7 1, 14, 21, 28, 35
the least distance 21-20=1. or 15-14=1
so desired answer 1/35
- selango
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Large tick marks are divided into fifths:1/5,2/5,3/5,4/5,5/5
Small tick marks are divided into sevenths:1/7,2/7,3/7,4/7,5/7,6/7,7/7
LCM(5,7)=35 and have a common denominator on both terms.
-->Large tick marks:7/35,14/35,21/35,28/35,35/35
-->Small tick marks:5/35,10/35,15/35,20/35,25/35,30/35,35/35
Least distance =21/35-20/35=1/35
Small tick marks are divided into sevenths:1/7,2/7,3/7,4/7,5/7,6/7,7/7
LCM(5,7)=35 and have a common denominator on both terms.
-->Large tick marks:7/35,14/35,21/35,28/35,35/35
-->Small tick marks:5/35,10/35,15/35,20/35,25/35,30/35,35/35
Least distance =21/35-20/35=1/35
--Anand--