SOLUTION: Hi can someone help with this question please The first of two men can dig out a hole in 2 hours. The second man can dig out 3 holes of the same size in 4 hrs. How many minutes w

Algebra ->  Finance -> SOLUTION: Hi can someone help with this question please The first of two men can dig out a hole in 2 hours. The second man can dig out 3 holes of the same size in 4 hrs. How many minutes w      Log On


   

Question 1155946: Hi can someone help with this question please
The first of two men can dig out a hole in 2 hours. The second man can dig out 3 holes of the same size in 4 hrs. How many minutes will it take for both men to dig a single hole together?



Thanks in advance
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Rate of working for the 1st man:
[ 1 hole ] / [ 2 hrs ]
Rate of working for the 2nd man:
[ 3 holes ] / [ 4 hrs ]
Rate of working with both:
[ 1 hole ] / [ t hrs ]
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+1%2F2+%2B+3%2F4++=+1%2Ft+
Multiply both sides by +4t+
+2t+%2B+3t+=+4+
+5t+=+4+
+t+=+4%2F5+ hrs
+t+=+%284%2F5%29%2A60+=+48+
They will take 48 min working together
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check:
+1%2F2+%2B+3%2F4++=+1%2Ft+
+.5+%2B+.75+=+1%2F%284%2F5%29+
+5%2F4+=+5%2F4+
OK