Page 146 - NUMINO Challenge_B1

Problem solving 3 If you use , , and in the given order, the

1 To get the smallest answer, the number or the divisor becomes 1, and the multiplier becomes
9. If you divide by the smallest number and
divisor should be as great as possible. The multiply by the greatest number, the equation
subtracted number is the greatest number, will result in the greatest possible answer. The
(100 30 6) 105. Therefore, equation is (7 8) 9 1 135.
1000 (100 30 6) 895. Instead of dividing
only 30 by 6, divide 1000 100 30 by 6 to 4 9 9 18, 9 9 0, 9 9 81, 9 9 1
result in a smaller value. Place the parentheses
around 100 30 to result in 1000 (100 30). Using these equations above, you can write the
The final equation that results in the smallest
answer is {1000 (100 30)} 6 145. equations 18 1 19, 81 1 80, 81 0 81.

2 The first part is 6 3 10 20. In order for the Therefore, 9 9 9 9 19, 9 9 9 9 80, and

equation to work out, the first part must be 9 9 9 9 81.
divided by 20 to equal 1. Therefore,
parentheses must be placed around (4 6 4), (9 9) 9 2 9 2 7 9 (9 9) 9 7
to get 20 20 1.
(9 9) 9 0 9 0 9 9 (9 9) 9 9
6 3 10 (4 6 4) 1
(9 9 9 90 90 9 10 (9 9 9) 9 10

99 9 11 11 9 20 99 9 9 20

9 9 9 729 729 9 720 9 9 9 9 720

Creative Thinking p.30~p.31

1 Using 5 5 1, you can make:

5 1 1 4 5 (5 5) (5 5) 4
5113 555553

Using (5 5) 5 2, you can make
2 1 2 (5 5) 5 5 5 2
2 1 1 (5 5) 5 5 5 1
Answers will vary.

2 Since 3 8 24, form an equation using 9, 2,

and 3 with an answer of 3.
9 2 3 8 24.

Answer Key