TÝnh nhanh ph©n sè
Bµi 1: TÝnh nhanh:

15151515
31313131
454545
989898
−
=
101010115
101010131
1010145
1010198
x
x
x
x
−
=
45
98
-
15
31
=
45
98
-
45
93
=

199419961000
996119941996
×+
−+×
=
×+
−+×
=
199419961000
100019941996
×+
+×
=
= 1(v× tö sè b»ng mÉu sè)
a) Tính nhanh:
1997 1998 1
1998 1996 1997
× −
× +
=
a)
199619971995
119961997
+×
−×
253399254
145399254
)
×+
−×

48
24
48
24
1
23
24
48
23
37
53
53
37
23
24
37
53
48
23
53
37
1010123
1010124
1010137
1010153
48
23
53
37
==×=

2008
2006
)
5
7
200019991998
120011999
)
××××
×
×+
−×
b
a
Bµi 5: TÝnh nhanh
1000
99
1000
87
...
1000
49
1000
37
1000
25
1000
13
1000
1