Page 160 - NUMINO Challenge_B1

Rules for Shapes 2 9 matches are needed to make the first cube. 5

10 Rules for the Number of Shapes p.86~p.87 matches are needed to make one more cube.
Therefore, 9 5 (10 1) 54 matches are
needed to make 10 cubes.

Example 5, 4 5, 4, 41 Type 10-2 Difference Between the Number of Stones p.90~p.91

Example 1

Squares 2 2 3 3 4 4 5 5 By the th row 2nd 4th 6th 8th

Stones

Number of White Stones 4(2 2) 9(3 3) 16(4 4) 25(5 5) Number of Black Stones 2 6 12 20

Number of Black Stones 1(1 1) 4(2 2) 9(3 3) 16(4 4) Number of White Stones 1 4 9 16

Difference 3579 Difference 1234

2, 5, 7, 9 11, 13 2 There is 1 more black stone by the 2nd row, 2
more black stones by the 4th row, and 3 more
Type 10-1 Constant Increase in the Number of Shapes p.88~p.89 black stones by the 6th row. Following this
pattern, there are 4 more black stones by the
1 Number of Times Cut 1 2345 8th row and 5 more black stones by the 10th
7 10 13 16 row.
Number of Thread Pieces 4
3 When there are n rows, there are n 2 more
2 The number of thread pieces increases by 3. black stones. Therefore, there are 10 more black
stones by the 20th row.
3 Number of thread pieces when cut times
4 3 ( 1) Problem solving

4 Number of thread pieces when cut 10 times 1
4 3 (10 1) 31 pieces

Number of black stones 4 6 8 10

Problem solving Number of white stones 1 2 3 4

1 Difference 3456

Number of Times Cut 1 2 3 4 5 The difference between the number of black and
Number of Thread Pieces 5 9 13 17 21 white stones in the nth arrangement is n 2.
Therefore, the difference in the tenth
44 4 4 arrangement is 10 2 12.
Therefore, the number of thread pieces when
cut 10 times 5 4 (10 1) 41 pieces.

Answer Key