SOLUTION: A shipment of TV sets, some weighing 30 kg each and the others weighing 50 kg each, has a total weight of 880 kg. If there are 20 TV sets all together, how many weigh 50 kg?

Algebra ->  Customizable Word Problem Solvers  -> Numbers -> SOLUTION: A shipment of TV sets, some weighing 30 kg each and the others weighing 50 kg each, has a total weight of 880 kg. If there are 20 TV sets all together, how many weigh 50 kg?       Log On

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Question 941717: A shipment of TV sets, some weighing 30 kg each and the others weighing 50 kg each, has a total weight of 880 kg. If there are 20 TV sets all together, how many weigh 50 kg?

Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
Lighter TV sets=L Heavier sets =H
L+H=20
30L+50H=880
Solve first equation for H and substitute in second
H=20-L
30L+50(20-L)=880
30L+1000-50L=880
-20L+1000=880 divide both sides by -20
(-20L+1000)/-20=880/-20
L-50=-44 add 50 to each side
L-50+50=-44+50
L=6 ANSWER 1 there were 6 of the lighter sets
H=20-L=20-6=14 ANSWER 2 there were 14 of the heavier sets
CHECK:
30 kg(L)+ 50 kg(H)= 880 kg
30 kg (6) +50 kg (14)=880 kg
180 kg + 700 kg=880 kg
880 kg=880 kg