A farmer owns several dairy cows, some black, some brown. He finds that 4 black cows and 3 brown cows give the same amount of milk in 5 days as 3 black cows and 5 brown cows give in 4 days. Which gives more milk in a day, a black or brown cow? Show work/explain.
CAn you come up with a rectangle whose sides are whole numbers and whose area is numerically equal to its perimeter? There are 2 solutions.
Let Y be the amount of milk a brown cow produces each day.
Therefore, 1 black cow produces 5X of milk in 5 days. So 4 black cows will produce 4x5X=20X in 5 days.
Similarly, 3 brown cows will produce 3x5Y=15Y of milk in 5 days.
From the second part (in 4 days), 3 black cows will produce 3x4X=12X of milk in 4 days.
5 brown cows will produce 5x4Y=20Y of milk in 4 days.
Therefore, you have the equality : 20X+15Y=12X+20Y
After some calculations, you should get 8X=5Y
I think you can conclude