It takes machine A x hours to manufacture a deck of cards that machine B can manufacture in y hours. If machine A operates alone for z hours and is then joined by machine B until 100 decks are finished, for how long will the two machines operate simultaneously?
A) 100xy - z/
x + y
b) y(100x - z)/
x + y
c) 100y(x - z)/
x + y
d) x + y /
100xy - z
ans is B
e)
x + y - z/
100xy
A) 100xy - z/
x + y
b) y(100x - z)/
x + y
c) 100y(x - z)/
x + y
d) x + y /
100xy - z
ans is B
e)
x + y - z/
100xy
