SOLUTION: when young MacDonal was starting his farm a long time ago,cows cost $10 each,pigs cost $3 each and chickens cost $0.50 each. He puechsed at least one of kind of animal. He paid $10
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-> SOLUTION: when young MacDonal was starting his farm a long time ago,cows cost $10 each,pigs cost $3 each and chickens cost $0.50 each. He puechsed at least one of kind of animal. He paid $10
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Question 160102: when young MacDonal was starting his farm a long time ago,cows cost $10 each,pigs cost $3 each and chickens cost $0.50 each. He puechsed at least one of kind of animal. He paid $100 for exatly 100 animals. HOW MANY CHICKENS DID HE BUY? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! If cows cost $10 each, pigs cost $3 each and chickens cost $0.50 each. He got at
least one of kind of animal. He paid $100 for exactly 100 animals.
HOW MANY CHICKENS DID HE BUY?
:
x = no. cows
y = no. pigs
z = no. of chickens
:
Total animal equation
x + y + z = 100
:
Total cost equation
10x + 3y + .5z = 100
:
Multiply the above equation by 2 and subtract the 1st equation (total animals)
20x + 6y + 1z = 200
x + y + 1z = 100
-----------------------subtraction eliminates z
19x + 5y = 100
Arrange equation in the general y= form
5y = 100 - 19x
y = 20 - x; divided both sides by 5
:
Study this equation and it's apparent the only value for x that will give a
positive integer value for y, is x = 5
:
y = 20 - *5
y = 20 - 19
y = 1 pig
:
We have 5 cows, 1 pig
Find chickens: 100 - 5 - 1 = 94 chickens
:
Check:
10(5) + 3(1) + 94(.5) =
50 + 3 + 47 = 100
