maths

posted by .

Mr Tan had a box of marbles. 2/3 of the marbles were blue and the rest were yellow. He gave his son 4/5 of the blue marbles and 3/4 of the yellow marbles. If he had 39 marbles left, how many marbles did he have at first?

  • maths -

    X = total mrbles.
    2x/3 Blue marbles.
    x/3 yel. marbles.

    X - 4/5(2x/3) - 3/4(x/3) = 39 Marbles.
    X - 8x/15 - x/4 = 39.
    Multiply both sides by 60:
    60x - 32x - 15x = 2340.
    60x - 47x = 2340.
    13x = 2340.
    X = 180 Marbles.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Probabilities

    A jar contains 2 red marbles, 3 green marbles, 4 blue marbles, and 5 yellow marbles. Two marbles are drawn in succession, without replacement. The probability that neither is yellow?
  2. statistics

    From a jar of marbles containg 4 blue marbles, 3 yellow marbles, 2 red marbles, and 1 magenta marble, you draw two marbles with replacement. Determine the following probablilites. a. P( red then blue) b. P(yellow and yellow) c. P(red/yellow) …
  3. Math

    a bag contains 3 red marbles, 5 blue marbles, 2 yellow marbles, and 2 lavender marbles. How many sets of 4 marbles includes at most one of the yellow marbles?
  4. probability

    A set of five marbles is selected (without replacement) from a bag that contains 4 blue marbles, 3 green marbles, 6 yellow marbles, and 7 white marbles. How many sets of five marbles contain no more than two yellow ones?
  5. Algebra

    A jar contains red, blue and yellow marbles.The number of red marbles is ten more than the number of yellow marbles and the number of blue marbles is double the number of yellow marbles. If the probability of choosing a yellow marble …
  6. maths algebra

    A bag contains x marbles,1\2 of the marbles were red,1\d were blue and the rest were yellow write down expressions for the quantity of red marbles the quantity of blue marbles and the quantity of yellow marbles
  7. Math

    I am having a problem answering this math problem. Andrea has a box of marbles in it. She has seven red marbles, thirteen blue marbles and nineteen yellow marbles. If she reaches in and takes out marbles without looking, what is the …
  8. Math "Need Help Asap"!

    1.)There are 35 marbles in a bag:9 blue marbles, 8 marbles, 4 red marbles, 4 red marbles, 8 white marbles, & 6 yellow marbles. Find P(Red). Write the probability as a fraction in simplest form, a decimal, & a percent. A.)4/31, 0.129, …
  9. Maths

    A bag contains marbles of three different colours red, blue , yellow. 2/5 of the marbles are red. The ratio of the number of blue marbles to the number of yellow marbles is 5:7. What fraction of the marbles in the bag is blue?
  10. Math

    Ken had a number of colored marbles in a bag. 1/4 of the marbles were red, 2/3 of the remaining marbles were blue, and the rest were yellow. Given that there were 120 red and yellow marbles altogether, how many marbles were there in …

More Similar Questions