There were 90 marbles in 3 bags, P, Q, and R. Jane moved 6 marbles from Bag P to Bag Q and 5 marbles from Bag Q to Bag R. He then moved 31 marbles from Bag R to Bag P. There were an equal number of marbles in each bag in the end. How many marbles were there in Bag Q at first?
Q. There were 90 marbles in 3 bags, P, Q, and R. Jane moved 6 marbles from Bag P to Bag Q and 5 marbles from Bag Q to Bag R. He then moved 31 marbles from Bag R to Bag P. There were an equal number of marbles in each bag in the end. How many marbles were there in Bag Q at first?
Equation Setup: Let's denote the initial number of marbles in Bags P, Q, and R as P, Q, and R respectively. We know that the total number of marbles is 90, so we can write the equation:P+Q+R=90
Move Marbles: P to Q: Jane moved 6 marbles from Bag P to Bag Q, so now Bag P has P−6 marbles, and Bag Q has Q+6 marbles.
Move Marbles: Q to R: Then, Jane moved 5 marbles from Bag Q to Bag R, so Bag Q now has Q+6−5=Q+1 marbles, and Bag R has R+5 marbles.
Move Marbles: R to P: Finally, Jane moved 8 marbles from Bag R to Bag P, so Bag R now has R+5−8=R−3 marbles, and Bag P has P−6+8=P+2 marbles.
Equal Marbles in Bags: After all the movements, each bag has an equal number of marbles. Therefore, we can set the expressions for the number of marbles in each bag equal to each other:P+2=Q+1=R−3
Total Marbles Calculation: Since the total number of marbles is still 90, we can use the equation from the first step and substitute the expressions for P, Q, and R:(P+2)+(Q+1)+(R−3)=90
Marbles Distribution: Simplifying the equation, we get:P+Q+R=90P+2+Q+1+R−3=90P+Q+R=90−2−1+3P+Q+R=90This confirms that the total number of marbles remains unchanged.
Find Initial Marbles in Q: Now, we know that each bag has an equal number of marbles, so we can divide the total number of marbles by 3 to find out how many marbles each bag has after the movements:90 marbles /3 bags =30 marbles per bag
Find Initial Marbles in Q: Now, we know that each bag has an equal number of marbles, so we can divide the total number of marbles by 3 to find out how many marbles each bag has after the movements:90 marbles / 3 bags = 30 marbles per bagWe can now express the initial number of marbles in Bag Q (which we are trying to find) in terms of the final number of marbles in each bag:Q+1=30
Find Initial Marbles in Q: Now, we know that each bag has an equal number of marbles, so we can divide the total number of marbles by 3 to find out how many marbles each bag has after the movements:90 marbles / 3 bags = 30 marbles per bagWe can now express the initial number of marbles in Bag Q (which we are trying to find) in terms of the final number of marbles in each bag:Q+1=30Solving for Q, we subtract 1 from both sides of the equation:Q=30−1Q=29