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Jo can mow a lawn in 50 minutes.  Chris can mow the samelawn in 30 minutes.  How many minutes will it take the two of them to mow it if both are mowing at the same time?

 May 4, 2020
 #1
avatar+111326 
+1

Actually....it's really easy to solve this kind of problem  !!!

 

Note  that Jo  mows  1/50  of  the yard in one minute  and Chris mows 1/30  of the yard in one minute

 

So   add these fractions

 

1/50  + 1/30   =   [ 30 + 50 ] / 1500  =   80  /150   =   8/15

 

Take  the reciprocal....this is the time it will take if both work together

 

15/8  =   [ 1 + 7/8 ] hrs  

 

And  7/8  hrs   =  (7/8)*60   =  52.5 min

 

So    60  + 52.5     =    112.5 min

 

 

cool cool cool   

 May 4, 2020
 #2
avatar+657 
+1

Great Work CPhill!

LuckyDucky  May 4, 2020
 #3
avatar+111326 
+1

Thanks, LD  !!!!

 

 

cool cool cool

CPhill  May 4, 2020
 #4
avatar+657 
+2

Ce n'est pas un problème

 

Lol I'm learning french

 

coolsmileycool

LuckyDucky  May 4, 2020

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