Date: 11/15/1999 at 15:45:54 From: Kyersten Subject: Delivering Papers Uri delivers 5 newspapers in the same time Juni delivers 4 newspapers. If they have a total of 54 papers, how many will Uri deliver? How many will Juni deliver?
Date: 11/15/1999 at 19:14:24 From: Doctor Ian Subject: Re: Delivering Papers Hi Kyersten, There is a general way to solve this, but what your teachers don't often tell you is that the 'general' method isn't always the best. (For example, if you want to add 49 and 2, you can carry the one, or you can say to yourself: '50, 51.') In this case, because the numbers are small, you can just do a simulation: Time Uri Juni Total ---- --- ---- ----- 1 5 4 = 9 2 10 8 = 18 3 15 12 = 27 4 20 16 = 36 Can you complete this on your own? Another way to solve the problem, which doesn't involve so much writing, is to realize that in each unit of time, a total of 9 papers will get delivered: 5 by Uri, 4 by Juni. Since you know that the total number of papers to be delivered is 54, you can divide 54 by 9 to get the number of units of time. Then you can multiply this by 5 to find out how many were delivered by Uri, and multiply by 4 to find out how many were delivered by Juni. For example, if they were delivering 72 papers, they would finish in 72/9 = 8 units of time. That would mean that Uri would deliver 8*5 = 40 papers, and Juni would deliver 8*4 = 32 papers. Can you take it from here? Be sure to write back if you're still stuck, or if you have any other questions. - Doctor Ian, The Math Forum http://mathforum.org/dr.math/
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