there are boxes containing 5 , 7 , 14 , 16 , 18 , 29 balls of either red or blue in colour. Some boxes
contain only red balls and others contain only blue . One sales man sold one box out of them
and then he says " I have the same number of red balls left out as that of blue ".
Which box is the one he solds out ?

• the box containing 29 balls is sold.
  proof- total no. of ball=5+7+14+16+18+29=89
  so to have equal no of red and blue ball we need to sell the box containing odd no of ball. but to choose to odd box we must check if the remaining boxes can be divided in to groups such that there are equal no of balls in each group.
  ie. by selling the box containing 29 ball the remaining boxes ca be divided into 7+5+18(30) and 14+16(30).
• 13 years agoHelpfull: Yes(3) No(0)