Page 137 - NUMINO Challenge_D2
P. 137
Creative Thinking
1 There are several red marbles in a box. After putting 40 blue marbles
in the box and mixing them well, there are 15 red marbles and 20 blue
marbles remaining in the box when 25 marbles are taken out from the
box. How many red marbles were in the box in the beginning?
40 blue 25 marbles
marbles
2 A merchant needs to pass through three doors in order to get into the
castle, but there is a guard in front of each door. The guard at the first
door lets the merchant pass through if the merchant gives one more
coin than half of the coins he has. Also, the guards at the second and
third doors allow him to pass through if he gives one more coin than
half of the coins he has. If the merchant is left with one coin after
passing through all three doors and entering the castle, how many
coins did he have in the beginning?
134 NUMINO Challenge D2
1 There are several red marbles in a box. After putting 40 blue marbles
in the box and mixing them well, there are 15 red marbles and 20 blue
marbles remaining in the box when 25 marbles are taken out from the
box. How many red marbles were in the box in the beginning?
40 blue 25 marbles
marbles
2 A merchant needs to pass through three doors in order to get into the
castle, but there is a guard in front of each door. The guard at the first
door lets the merchant pass through if the merchant gives one more
coin than half of the coins he has. Also, the guards at the second and
third doors allow him to pass through if he gives one more coin than
half of the coins he has. If the merchant is left with one coin after
passing through all three doors and entering the castle, how many
coins did he have in the beginning?
134 NUMINO Challenge D2
