1. 3
2 (12 )
3.1 (6 )
3.2 (3 )
3.3 (3 )
3.1 3.2
3.3
1 1 1
1
1.
2.

2. 47
3.1 (6 )
1.
2.
3.
3.1
1.
2. “ ”
3.
2 – 3
1)
111 – 101 = 10
252 – 242 = 10
2)
313 – 212 = 101
535 – 434 = 101
47

3. 48
3)
909 – 111 = 798
949 – 151 = 798
4. “ ” 11
11
a b a 0
abba
abba = (a 103
) + (b 102
) + (b 10) + (a 1)
= 1000a + 100b + 10b + a
= 1001a + 110b
11
abba =
11
1001a +
11
110b
= 91a + 10b
a b
91a 10b
91a + 10b
abba 11
11
5. “ ”
“ 0 ”
10012
= 1002001 “0”
1 1 “0” 1 2 2 1
6. “ ”
98
24 13 8813200023188
7. “ ”
48

4. 49
1 81 999999999
8.
“ ” 3.1
9. “ ”
10. “ ”
4 – 5 30
n
2
1)-n(n
11. “ ” “IPST Cup”
49

5. 50
3.2 ( 3 )
1.
2.
3.2
1.
2. “ ”
F C
F C
3. “ ”
4. 0 2
5. 3.2 4
3.2
6. “ ”
1
50

6. 51
3.3 (3 )
1.
2.
1.
2.
3. 3.3 1
4. 7 3.3
1.45
1.75
1 1.75 – 1.45 = 0.30
0.30 1
39 39
300
1
.
= 130
51

7. 52
12
130 + 12 = 142
39
12 12
142
5. “ ” 1
2
173
173
1 6 125 19
9 1 9 6 125 20
5 6 20 5
3
52

8. 53
“ ”
1.
101 111 121 131 141 151 161 171 181 191
202 212 222 232 242 252 262 272 282 292
303 313 323 333 343 353 363 373 383 393
404 414 424 434 444 454 464 474 484 494
505 515 525 535 545 555 565 575 585 595
606 616 626 636 646 656 666 676 686 696
707 717 727 737 747 757 767 777 787 797
808 818 828 838 848 858 868 878 888 898
909 919 929 939 949 959 969 979 989 999
2. 90
3.
4. 90
5. 1 9
1
1 0 9
53

9. 54
“ ”
1.
1001 1111 1221 1331 1441 1551 1661 1771 1881 1991
2002 2112 2222 2332 2442 2552 2662 2772 2882 2992
3003 3113 3223 3333 3443 3553 3663 3773 3883 3993
4004 4114 4224 4334 4444 4554 4664 4774 4884 4994
5005 5115 5225 5335 5445 5555 5665 5775 5885 5995
6006 6116 6226 6336 6446 6556 6666 6776 6886 6996
7007 7117 7227 7337 7447 7557 7667 7777 7887 7997
8008 8118 8228 8338 8448 8558 8668 8778 8888 8998
9009 9119 9229 9339 9449 9559 9669 9779 9889 9999
2. 90
“ ”
1.
112
= 121
1012
= 10201
10012
= 1002001
100012
= 100020001
1000012
= 10000200001
10000012
= 1000002000001
2. 1000000000012
= 10000000000200000000001
54

10. 55
3.
222
= 484
2022
= 40804
20022
= 4008004
200022
= 400080004
2000022
= 40000800004
20000022
= 4000008000004
4. 2000000000022
= 40000000000800000000004
“ ”
14 56
59 67
14
41
55
56
65
121
+ +
59
95
154
451
605
506
1111
67
76
143
341
484
+
+
+
+
+
55

11. 56
“ ”
1. 12345679 9 = 111111111
12345679 18 = 222222222
12345679 27 = 333333333
12345679 36 = 444444444
12345679 45 = 555555555
2. 8 + (9 0) = 8
7 + (9 9) = 88
6 + (9 98) = 888
5 + (9 987) = 8888
4 + (9 9876) = 88888
“ ”
1. 13, 21, 34, 55 89
2.
1) 377 2) 987 3) 4181
“ ”
1. 1
2. 3
3. 6
3
2
1
6
4. 30
56

12. 57
86
5. 10 (0 + 1 + 2 + 3 + 4)
6. 15 (0 + 1 + 2 + 3 + 4 + 5)
87
1. 21 2. 45
“ ”
1. 10 2. 10 3. 28
“IPST Cup”
15
1 2 4 2 6 = 12
2 2 2 2
2 2 1
12 + 2 + 1 = 15
“ ”
1.
1) 3)
2) 4)
2.
1) A B –
2) – A, B C
3) B C A D
4) C D A, B, E F
57

13. 58
“ ”
1.
1)
0
2) 0
3) 2
4) 2
5) 2
(6) 4
(7) 6
(8) 4
58

14. 59
2. 0 2
3. 1
2
1) 0
2) 0
3) 2
4) 2
5) 2
(6) 4
59

15. 60
(7) 6
(8) 4
3.2
1.
1) 2 2) 0
3) 0 4) 4
60

16. 61
5) 2 6) 4
2.
3.
2
61

17. 62
4.
1) ( 0) 2) ( 0)
3) ( 2) 4) ( 2
)
“ ”
1. 4
2.
3.
3.3
1.
1)
4
14- 2)
10
365
3)
4
316- 4)
8
522
5)
2
146- 6)
12
528
7)
12
115- 8)
10
111
9) 5 10)
20
9
11) 17.75 12) 519
13) 1 14) 8.8
2. 170.50
= 2(29 + 12.50 + 17.75) + 0.5 (59 + 45)
= 2 (29 + 12.50 + 17.75) +
2
1 (59 + 45)
= 118.50 + 52
= 170.50
3. 87.6
4. 21,053.40
62

18. 63
5. 83,850
1 15.16
227.4 227.4 15.16 = 15
5
2
5
3
4,580 6,930
6,93015
5
34,58015
5
2
= 27,480 + 62,370
= 89,850
15 400 15 400
= 6,000
89,850 – 6,000
= 83,850
6. 1457.89
7. 200
1 x 1.45 1.45x
x – 12 1.75 1.75 (x – 2)
1.75 (x – 12) – 1.45x = 39
1.75x – 21 – 1.45x = 39
0.30x = 60
x = 200
200
2
12
39
12 1.75 12 = 21
39 + 21 = 60
0.30 1
60
300
60
.
= 200
63

19. 64
“ ”
1.
( )
2
1
3
1
10 0
8 3
5 6 6
4 9
2 12
0 15
6 2
4 5
2 8
0 11
8 1
5 1
1 8
2. 170
75 125
6 9
6 9
3
23
6
12
64

20. 65
1
(1 11) + (19 7) + (12 2) + (1 2) = 170
2
(9 11) + (7 7) + (1 14) + (4 2) = 170
9 9 6 7
9 4
6 2
9 7
6 11
6 14
9 1
9 11
1 14 4 2
7 7
6 2
6 19
9 12
12 2 9 1
9 1
6 11
6 2
1 2
9 7
111
19 7
65

21. 66
3
(5 12) + (5 18) + (1 12) + (1 8) = 170
3.
4
15
4
15 a
2
15
4
15 b
2
112
4
310 c
2
110
4
15 d
2
112
4
15 e
7
16 23
4
15
4
15
4
15
4
15
2
110
2
112
4
15
2
112
4
310
2
15 b
a
b
a
d
c
e
6 5
6 18
9 12
9 5
2 .
5 18
5 12
18
72
3 .
112
66

22. 67
3.1
…
67

23. 68
3.2
A
B
A B
1
2
3
4
5
6
7
8
9
10
A B
68