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Gage
New Member

USA
1 Posts

 Posted - 01/02/2012 :  19:08:45 1/5, -3/10, 7/6, 3/4, -1/2Use these fractions below to make equations true.______+_______+______=-1/12. How do I solve these type equations I have ten of them to do.

the_hill1962

USA
1468 Posts

the_hill1962

USA
1468 Posts

 Posted - 01/04/2012 :  11:41:30 There is no way to take a combination of three of the numbers12, -18, 70, 45, -30to add to be -5. Therefore, the problem can't be done unless I have done something wrong in my previous post OR you are allowed to use more than just 3 of the numbers in the sum.I do find that 12*4 + (-30)*2 + 70*4 + (-18)*16 + 45*1 + (-30)*1 = -5This means that adding the following should be -1/12:Four of the 1/5Two of the -1/2Four of the 7/6Sixteen of the -3/10One of the 3/4One of the -1/2You may be wondering how I figured out12*4 + (-30)*2 + 70*4 + (-18)*16 + 45*1 + (-30)*1 = -5If so, I just first saw that 45-30=15 so if I could find a combination that summed to -20, it would be 15+(-20)=-5.I saw that 12+12-30=-6 and then experimented with the combination of 70 and -18. I eventually thought 140 minus several 18s would get -4.(that is 140-18*8=-4) and thus combining that -4 with the -6 gives -10. TWO of those would make -20 (as was needed for 15+(-20)=-5.I hope this helps.If anyone sees a better way to do this problem, please post! Edited by - the_hill1962 on 01/04/2012 12:05:39
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