I have always been very good at math and algebra, but for some reason these types of questions keep giving me problems. Any suggestions on what to do for these types? After seeing how to do the problem, I understand it, but keep makin the same mistakes. What messes me up are when there are multiple variables in the question. I usually sub in some numbers, but it gets confusing at the end when there are variables in the answers.
If m > 0, y > 0, and x is m percent of 2y, then, in terms of y, m is what percent of x?
y/200
2y
50y
50/y
5000/y
90 students represent x percent of the boys at Jones Elementary School. If the boys at Jones Elementary make up 40% of the total school population of x students, what is x?
125
150
225
250
500
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?
y(100x – z) /(x + y)
If m > 0, y > 0, and x is m percent of 2y, then, in terms of y, m is what percent of x?
y/200
2y
50y
50/y
5000/y
90 students represent x percent of the boys at Jones Elementary School. If the boys at Jones Elementary make up 40% of the total school population of x students, what is x?
125
150
225
250
500
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?
y(100x – z) /(x + y)
