+36 David had two bags of marbles. After he sold 44 marbles from bag X to his friend, the number of marbles in bag Y was 5/7 of the marbles in bag X. Given that there were 2/5 as many marbles in bag Y as in bag X originally, how many marbles were there in bag X at first.
+130037 Originally we have that :
(2/5)X =Y (1)
After he sells 44 marvles from bag X, we have this situation :
(5/7) (X -44) = Y (2)
Sub (2) into (1)
(5/7)(X -44) =(2/5)X
(5/7)X - 220/7 = (2/5)X
[ 5/7 - 2/5 ] X = 220/7
[ 11/35]X = 220/7
X = 220/7 * 35/11 =100 marbles originally in X
Check
Otiginally
X =100
Y = (2/5) 100 = 40
After he sells 44 marbles from X we have that
X = (5/7)(100 - 44) = (5/7) (56) = 40 = the number in Y = (2/5)*100
