Page 156 - NUMINO Challenge_C1

2 1 cm 4 To make the smallest area of a rectangle, the
1 cm
longest sides should be mostly connected. Since
6 5 30 cm2 the six faces of the rectangular prism are

33

2 3,
there are two ways to connect the long sides
using four sides of six.

Creative Thinking p.74~p.75 33

22 2 2 3 23 2

1 To get the greatest sum, color the numbers in In , the net cannot be drawn by connecting

order from the greatest. the remaining two faces. Therefore, the area of

1 12 11 10 the smallest rectangle containing a cube net is
2 13 16 9
3 14 15 8 the area of the rectangle containing the cube
45 67
net made by connecting the remaining two
11 10 16 14 15 6 72
faces to , 10 7 70 cm2.
2
7 cm
10 cm

Front Right 9 The Dice “Rule of Seven” p.76~p.77

3A B E Example 5 5, 2 Back
CD
N FG
IH
Try It Again

M LK Left
J

If you connect the vertices that touch each other Base
when the net is folded, point A will meet with
points E and G.

Example 3, 1, 2, 4, 5, 6, 18 7, 21, 7, 14
18, 14, 32

TryItAgain The total number of pips on one die is 21.
The sum of pips on the sides that meet is
5 3 8. Therefore, the total number of
pips that can be seen from the outside is
21 2 8 34.

Answer Key