Answer: one puppy weighs 5 pounds
Step-by-step explanation:
Let the weight of one puppy be x and the weight of adult dog be y.
Then from the first statement
3x + 3y = 60
Also from the second statement
4x + 2y = 50
combining the two equations together , we have
3x + 3y = 60 ............................... equation 1
4x + 2y = 50 ................................. equation 2
solving the system of linear equation by elimination method , multiply equation 1 by 4 and equation 2 by 3 , we have
12x + 12y = 240 ................................ equation 3
12x + 6y = 150 ....................................... equation 4
subtract equation 4 from equation 3
6y = 90
y = 15
substitute y = 15 into equation 1 to get the value of x.
3x + 3 ( 15 ) = 60
3x + 45 = 60
3x = 60 - 45
3x = 15
x = 5
1 puppy weighs 5 pounds and 1 adult dog weighs 15 pounds
