Page 134 - NUMINO Challenge_C2
P. 134
Problem solving Key Points
1 There is an ink that covers twice its area every It takes one drop of
second. If the ink covers an area of 1 now, it ink one second to
covers an area of 2 after one second, and an become two drops
area of 4 after two seconds. One drop of the ink of ink.
is dropped on a piece of paper. After four
seconds the entire paper is covered with ink.
How long will it take for two drops of ink to
cover the same paper?
2 A very fast spacecraft has been developed. This The distance
spacecraft travels faster than it did on the between the
previous day. Each day, the spacecraft travels the spacecraft and the
total distance it has traveled until the day before. Earth doubles every
The spacecraft leaves the Earth on January 1st day.
and reaches its destination, planet Gamma, on
December 31st. When will the spacecraft reach
planet Beta, which is halfway between the Earth
and planet Gamma?
Earth Planet Beta Planet Gamma
Jan. 1st ? Dec. 31st
131Communication
1 There is an ink that covers twice its area every It takes one drop of
second. If the ink covers an area of 1 now, it ink one second to
covers an area of 2 after one second, and an become two drops
area of 4 after two seconds. One drop of the ink of ink.
is dropped on a piece of paper. After four
seconds the entire paper is covered with ink.
How long will it take for two drops of ink to
cover the same paper?
2 A very fast spacecraft has been developed. This The distance
spacecraft travels faster than it did on the between the
previous day. Each day, the spacecraft travels the spacecraft and the
total distance it has traveled until the day before. Earth doubles every
The spacecraft leaves the Earth on January 1st day.
and reaches its destination, planet Gamma, on
December 31st. When will the spacecraft reach
planet Beta, which is halfway between the Earth
and planet Gamma?
Earth Planet Beta Planet Gamma
Jan. 1st ? Dec. 31st
131Communication
