[r]
Trang 1VIOLYMPIC TOÁN 5 – VÒNG 7 (23-11-2012) Tính nhanh:
1/ 42,75 × 39 – 42,75 × 29 =
2/ 1,986 × 41 + 1,986 × 59 =
3/ 20,08 × 2 + 20,08 × 8 =
4/ 1,386 × 194 – 1,386 × 94 =
5/ 0,028 × 93,27 – 0,028 × 83,27 =
6/ 29,34 × 87,56 – 29,34 × 77,56 =
7/ 28,54 × 3,8 + 28,54 × 6,2 =
8/ 1,1 × 20,9 – 20,9 =
9/ 265,3 × 0,06 + 265,3 × 0,04 =
10/ 26,9 × 28,41 – 26,9 × 28,4 =
11/ 14,58 × 7 + 14,58 × 3 =
12/ 37,91 × 39 – 37,91 × 29 =
13/ 8,192 × 154,09 – 8,192 × 54,09 =
14/ 58,07 × 6,78 – 58,07 × 6,68 =
15/ 20,08 × 2 + 20,08 × 8 =
16/ 0,396 × 74 + 0,396 × 26 =
17/ 25,86 × 17 – 25,86 × 7 =
18/ 0,924 × 142,9 – 0,924 × 42,9 =
19/ 0,384 × 12,3 + 0,384 × 87,7 =
20/ 1,369 × 23,9 + 1,369 × 76,1 =
21/ 12,84 × 1,8 – 12,84 × 1,7 =
22/ 815,5 × 0,08 + 815,5 × 0,02 =
23/ 1,01 × 68 – 68 =
24/ 2,305 × 108 – 2,305 × 8 =
25/ 1,472 × 81 + 1,472 × 19 =
26/ 84,03 × 58,27 – 84,03 × 48,27 =
27/ 9,75 × 3,81 + 9,75 × 6,19 =
28/ 8,175 × 104,3 – 8,175 × 4,3 =
Trang 229/ 1,01 × 2011 – 2011 =
30/ 1,472 × 81 + 1,472 × 19 =
31/ 0,028 × 186 – 0,028 × 86 = 32/ 8,175 × 104,3 – 8,175 × 4,3 = 33/ 93,57 × 19,45 – 93,57 × 9,45 = 34/ 19,8 × 58,4 + 19,8 × 41,6 =