SOLUTION: Tom can sort 280 nails in 2 hours and jerry can sort 120 nails in 3 hours how long will it take them to both sort 700 nails

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Question 698256: Tom can sort 280 nails in 2 hours and jerry can sort 120 nails in 3 hours how long will it take them to both sort 700 nails
Found 2 solutions by ankor@dixie-net.com, josmiceli:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Tom can sort 280 nails in 2 hours and jerry can sort 120 nails in 3 hours
how long will it take them to both sort 700 nails
:
Find the no. of nails per hr, each can sort
Tom: 280/2 = 140 per hr
Jer: 120/3 = 40 per hr
:
Let t = time (in hrs) required for both to sort 700 nails
140t + 40t = 700
180t = 700
t = 700/180
t = 3.89 hrs or 3 + .89(60) = 3 hrs 53 min

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Add their rates of nailing to get their rate
working together
Tom's rate: ( 280 nails ) / ( 2 hrs )
Jerry's rate: ( 120 nails ) / ( 3 hrs )
+280%2F2+%2B+120%2F3+=+700%2Fx+
++140%2F1+%2B+40%2F1+=+700%2Fx+
+700%2Fx+=+180+
+x+=+700%2F180+
+x+=+35%2F9+
+x+=+3.889+
+.889%2A60+=+53.333+
+.333%2A60+=+20+
Together, they can sort 700 nails in 3 hrs 53 min 20 sec
check answer:
++140%2F1+%2B+40%2F1+=+700%2Fx+
+180+=+700+%2F+3.889+
+700+=+700+
OK