C\u00e1ch ch\u01a1i n\u00e0y d\u1ef1a tr\u00ean nh\u1eefng d\u1eef ki\u1ec7n cho tr\u01b0\u1edbc, v\u00ec v\u1eady n\u00f3 c\u00f3 t\u1ef7 l\u1ec7 tr\u00fang th\u01b0\u1edfng c\u1ef1c cao, h\u1ea5p d\u1eabn, \u0111\u00e1ng ch\u1ecdn. N\u1ebfu anh em \u0111ang ch\u01b0a c\u00f3 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p ch\u01a1i n\u00e0o hi\u1ec7u qu\u1ea3 c\u00f3 th\u1ec3 th\u1ed1ng k\u00ea x\u1ed5 s\u1ed1, sau \u0111\u00f3 t\u00ecm ra c\u00e1c c\u1eb7p s\u1ed1 c\u1ef1c \u0111\u1eb9p.<\/p>\n
1. S\u1ed1 \u0111\u1ea7u \u0111u\u00f4i l\u00e0 g\u00ec? <\/strong><\/h2>\n<\/p>\n
\u0110\u00e1nh \u0111\u1ea7u \u0111u\u00f4i x\u1ed5 s\u1ed1 s\u1ed1 \u0111\u00e1nh \u0111\u1ec1 l\u00e0 c\u00e1ch \u0111\u00e1nh ch\u1eb7n v\u00f2ng gh\u00e9p s\u1ed1 t\u1eeb k\u1ebft qu\u1ea3 c\u1ee7a gi\u1ea3i n\u00e0y v\u1edbi s\u1ed1 kia c\u1ee7a gi\u1ea3i kh\u00e1c \u0111\u1ec3 c\u00f3 \u0111\u01b0\u1ee3c con s\u1ed1 \u0111\u00e1nh v\u00e0o ng\u00e0y h\u00f4m sau. \u0110\u00e1nh x\u1ed5 s\u1ed1 \u0111\u1ea7u \u0111u\u00f4i hay c\u00f2n \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 bi\u00ean 2 l\u00f4 \u0111\u1ea7u \u0111u\u00f4i. Khi \u0111\u00e1nh x\u1ed5 s\u1ed1 \u0111\u1ea7u \u0111u\u00f4i c\u00e1c b\u1ea1n s\u1ebd \u00e1p d\u1ee5ng theo quy lu\u1eadt lo\u1ea1i tr\u1eeb sau:<\/p>\n
Nh\u1eefng s\u1ed1 c\u00f3 0 h\u00e0ng \u0111\u01a1n v\u1ecb nh\u01b0: 10, 20, 30, 40, 50, 60, 70, 80, 90, 00 th\u00ec b\u1ecf kh\u00f4ng d\u00f9ng.<\/p>\n
Nh\u1eefng s\u1ed1 c\u00f3 s\u1ed1 0 \u1edf h\u00e0ng ch\u1ee5c nh\u01b0: 01, 02, 03, 04, 05, 06, 07, 08, 09 th\u00ec c\u0169ng kh\u00f4ng d\u00f9ng m\u00e0 b\u1ecf \u0111i.<\/p>\n
C\u00e1ch ch\u01a1i x\u1ed5 s\u1ed1 \u0111\u1ea7u \u0111u\u00f4i<\/h6>\n
T\u1ea5t c\u1ea3 c\u00e1c s\u1ed1 k\u00e9p, s\u1ed1 c\u1eb7p nh\u01b0: 11, 22, 33, 44, 55, 66, 77, 88, 99 c\u0169ng b\u1ecf qua t\u1ea5t c\u1ea3.<\/p>\n
Nh\u01b0 v\u1eady theo quy lu\u1eadt lo\u1ea1i b\u1ecf n\u00e0y c\u00e1c b\u1ea1n \u0111\u00e3 lo\u1ea1i b\u1ecf \u0111\u1ef1c 28 s\u1ed1 v\u00e0 c\u00f2n l\u1ea1i 72 s\u1ed1 ph\u1ea3i bi\u00ean. N\u1ebfu bi\u00ean 10 \u0111i\u1ec3m cho 71 s\u1ed1 s\u1ebd \u0111\u01b0\u1ee3c: 72\u00d710=720k. Trong \u0111\u00f3 ti\u1ec1n hoa h\u1ed3ng cho nh\u00e0 c\u00e1i \u0111\u01b0\u1ee3c t\u00ednh l\u00e0: 72 x 10 x 24.5% = 176.4k. Nh\u01b0 v\u1eady t\u1ed5ng s\u1ed1 ti\u1ec1n m\u00e0 c\u00e1c b\u1ea1n s\u1ebd m\u1ea5t l\u00e0 720k -176.4k = 543.6k.<\/p>\n
2. C\u00e1ch ch\u01a1i \u0111\u1ea7u \u0111u\u00f4i hi\u1ec7u qu\u1ea3 <\/strong><\/h2>\nC\u00f3 kh\u00e1 nhi\u1ec1u c\u00e1ch ch\u01a1i kh\u00e1c nhau, nh\u01b0ng t\u00f4i s\u1ebd gi\u1edbi thi\u1ec7u c\u00e1c b\u1ea1n ch\u01a1i theo 5 ph\u01b0\u01a1ng ph\u00e1p \u0111\u1ed9c \u0111\u00e1o, t\u1ef7 l\u1ec7 th\u1eafng cao sau \u0111\u00e2y:<\/p>\n
C\u00e1ch ch\u01a1i x\u1ed5 s\u1ed1 \u0111\u1ea7u \u0111u\u00f4i<\/h6>\nC\u01b0\u1ee3c theo \u0111\u1ea7u<\/h5>\n
Anh em c\u00f3 th\u1ec3 hi\u1ec3u \u0111\u01a1n gi\u1ea3n nh\u01b0 sau: V\u00ed d\u1ee5 h\u00f4m nay \u0111\u1ec1 v\u1ec1 61 ch\u00fang ta s\u1ebd c\u00f3 \u0111\u1ea7u 6, t\u1eeb \u0111\u00f3 gh\u00e9p v\u1edbi c\u00e1c s\u1ed1 t\u1eeb 0 \u2013 9 l\u00e0m \u0111u\u00f4i s\u1ebd c\u00f3 10 c\u1eb7p s\u1ed1 kh\u00e1c nhau. D\u00e0n s\u1ed1 n\u00e0y c\u00e1c b\u1ea1n c\u00f3 th\u1ec3 \u0111\u00e1nh l\u00f4 t\u1ef7 l\u1ec7 v\u1ec1 s\u1ebd cao nh\u1ea5t, m\u1ed9t s\u1ed1 b\u1ea1n l\u1ef1a ch\u1ecdn \u0111\u00e1nh \u0111\u1ec1 t\u1ef7 l\u1ec7 v\u1ec1 s\u1ebd th\u1ea5p h\u01a1n.<\/p>\n
C\u01b0\u1ee3c theo \u0111u\u00f4i<\/h5>\n
T\u00f4i c\u0169ng kh\u00e1 th\u00edch c\u00e1ch c\u01b0\u1ee3c n\u00e0y, t\u1ef7 l\u1ec7 v\u1ec1 kh\u00e1 cao. Tr\u00e1i v\u1edbi vi\u1ec7c gh\u00e9p v\u00e0o \u0111\u1ea7u, ch\u00fang ta s\u1ebd gh\u00e9p v\u00e0o \u0111u\u00f4i. N\u1ebfu gi\u1ea3i \u0111\u1eb7c bi\u1ec7t v\u1ec1 61 ch\u00fang ta l\u1ea5y \u0111u\u00f4i 1 gh\u00e9p v\u1edbi c\u00e1c s\u1ed1 t\u1eeb 0 \u2013 9. Nh\u01b0 v\u1eady s\u1ebd \u0111\u01b0\u1ee3c c\u00e1c c\u1eb7p 01, 11, 21\u2026 91. Ra m\u1ed9t d\u00e0n s\u1ed1 \u0111\u1eb9p kh\u00f4ng h\u1ec1 kh\u00f3 \u0111\u00fang kh\u00f4ng n\u00e0o. T\u00f4i v\u1eabn khuy\u00ean l\u00e0 l\u1ea5y d\u00e0n n\u00e0y \u0111\u1ec3 \u0111\u00e1nh l\u00f4 nha, \u0111\u00e1nh \u0111\u1ec1 th\u00ec d\u00f9ng d\u00e0n kh\u00e1c.<\/p>\n
C\u00e1ch ch\u01a1i x\u1ed5 s\u1ed1 \u0111\u1ea7u \u0111u\u00f4i<\/h6>\nGh\u00e9p v\u1edbi gi\u1ea3i 7<\/h5>\n
N\u1ebfu b\u1ea1n gh\u00e9p v\u1edbi gi\u1ea3i 7 s\u1ebd c\u00f3 \u00edt c\u1eb7p s\u1ed1 h\u01a1n, tuy nhi\u00ean ph\u01b0\u01a1ng ph\u00e1p n\u00e0y kh\u00e1 hay b\u1edfi anh em s\u1ebd s\u1eed d\u1ee5ng nhi\u1ec1u d\u1eef li\u1ec7u \u0111\u00e3 c\u00f3 h\u01a1n. \u0110\u1ec1 v\u1ec1 61, gi\u1ea3i 7 v\u1ec1 27, 35, 89 ch\u00fang ta s\u1ebd c\u00f3 d\u00e0n l\u00f4 nh\u01b0 sau: 67, 12, 65, 13, 69, 18 gh\u00e9p \u0111u\u00f4i gi\u1ea3i \u0111\u1eb7c bi\u1ec7t v\u1edbi \u0111\u1ea7u gi\u1ea3i 7, gh\u00e9p \u0111\u1ea7u gi\u1ea3i \u0111\u1eb7c bi\u1ec7t v\u1edbi \u0111u\u00f4i gi\u1ea3i 7 ch\u00fang ta s\u1ebd c\u00f3 c\u1eb7p s\u1ed1 c\u1ef1c hay \u0111\u1ec3 \u0111\u00e1nh.<\/p>\n
Gh\u00e9p v\u1edbi gi\u1ea3i 6<\/h5>\n
Gi\u1ea3i 6 s\u1ebd c\u00f3 nhi\u1ec1u c\u1eb7p s\u1ed1 h\u01a1n m\u1ed9t ch\u00fat, v\u00ec v\u1eady gh\u00e9p c\u0169ng ra nhi\u1ec1u s\u1ed1 \u0111\u1eb9p h\u01a1n. Ch\u1eb3ng h\u1ea1n \u0111\u1eb7c bi\u1ec7t v\u1ec1 44, gi\u1ea3i 6 v\u1ec1 52 59 01. Ch\u00fang ta s\u1ebd gh\u00e9p \u0111\u01b0\u1ee3c c\u00e1c c\u1eb7p s\u1ed1 sau: 54 42 49 04 41. Nh\u1eefng c\u00e1ch ch\u01a1i n\u00e0y \u0111\u01b0\u1ee3c m\u00ecnh lu\u00e2n phi\u00ean s\u1eed d\u1ee5ng v\u00e0 n\u00f3 c\u00f3 t\u1ef7 l\u1ec7 v\u1ec1 kh\u00e1 cao \u0111\u1ea5y.<\/p>\n
C\u00f3 kh\u00e1 nhi\u1ec1u c\u00e1ch ch\u01a1i kh\u00e1c nhau, nh\u01b0ng t\u00f4i s\u1ebd gi\u1edbi thi\u1ec7u c\u00e1c b\u1ea1n ch\u01a1i theo 5 ph\u01b0\u01a1ng ph\u00e1p \u0111\u1ed9c \u0111\u00e1o, t\u1ef7 l\u1ec7 th\u1eafng cao sau \u0111\u00e2y:<\/p>\n
C\u00e1ch ch\u01a1i x\u1ed5 s\u1ed1 \u0111\u1ea7u \u0111u\u00f4i<\/h6>\nC\u01b0\u1ee3c theo \u0111\u1ea7u<\/h5>\n
Anh em c\u00f3 th\u1ec3 hi\u1ec3u \u0111\u01a1n gi\u1ea3n nh\u01b0 sau: V\u00ed d\u1ee5 h\u00f4m nay \u0111\u1ec1 v\u1ec1 61 ch\u00fang ta s\u1ebd c\u00f3 \u0111\u1ea7u 6, t\u1eeb \u0111\u00f3 gh\u00e9p v\u1edbi c\u00e1c s\u1ed1 t\u1eeb 0 \u2013 9 l\u00e0m \u0111u\u00f4i s\u1ebd c\u00f3 10 c\u1eb7p s\u1ed1 kh\u00e1c nhau. D\u00e0n s\u1ed1 n\u00e0y c\u00e1c b\u1ea1n c\u00f3 th\u1ec3 \u0111\u00e1nh l\u00f4 t\u1ef7 l\u1ec7 v\u1ec1 s\u1ebd cao nh\u1ea5t, m\u1ed9t s\u1ed1 b\u1ea1n l\u1ef1a ch\u1ecdn \u0111\u00e1nh \u0111\u1ec1 t\u1ef7 l\u1ec7 v\u1ec1 s\u1ebd th\u1ea5p h\u01a1n.<\/p>\n
C\u01b0\u1ee3c theo \u0111u\u00f4i<\/h5>\n
T\u00f4i c\u0169ng kh\u00e1 th\u00edch c\u00e1ch c\u01b0\u1ee3c n\u00e0y, t\u1ef7 l\u1ec7 v\u1ec1 kh\u00e1 cao. Tr\u00e1i v\u1edbi vi\u1ec7c gh\u00e9p v\u00e0o \u0111\u1ea7u, ch\u00fang ta s\u1ebd gh\u00e9p v\u00e0o \u0111u\u00f4i. N\u1ebfu gi\u1ea3i \u0111\u1eb7c bi\u1ec7t v\u1ec1 61 ch\u00fang ta l\u1ea5y \u0111u\u00f4i 1 gh\u00e9p v\u1edbi c\u00e1c s\u1ed1 t\u1eeb 0 \u2013 9. Nh\u01b0 v\u1eady s\u1ebd \u0111\u01b0\u1ee3c c\u00e1c c\u1eb7p 01, 11, 21\u2026 91. Ra m\u1ed9t d\u00e0n s\u1ed1 \u0111\u1eb9p kh\u00f4ng h\u1ec1 kh\u00f3 \u0111\u00fang kh\u00f4ng n\u00e0o. T\u00f4i v\u1eabn khuy\u00ean l\u00e0 l\u1ea5y d\u00e0n n\u00e0y \u0111\u1ec3 \u0111\u00e1nh l\u00f4 nha, \u0111\u00e1nh \u0111\u1ec1 th\u00ec d\u00f9ng d\u00e0n kh\u00e1c.<\/p>\n
C\u00e1ch ch\u01a1i x\u1ed5 s\u1ed1 \u0111\u1ea7u \u0111u\u00f4i<\/h6>\nGh\u00e9p v\u1edbi gi\u1ea3i 7<\/h5>\n
N\u1ebfu b\u1ea1n gh\u00e9p v\u1edbi gi\u1ea3i 7 s\u1ebd c\u00f3 \u00edt c\u1eb7p s\u1ed1 h\u01a1n, tuy nhi\u00ean ph\u01b0\u01a1ng ph\u00e1p n\u00e0y kh\u00e1 hay b\u1edfi anh em s\u1ebd s\u1eed d\u1ee5ng nhi\u1ec1u d\u1eef li\u1ec7u \u0111\u00e3 c\u00f3 h\u01a1n. \u0110\u1ec1 v\u1ec1 61, gi\u1ea3i 7 v\u1ec1 27, 35, 89 ch\u00fang ta s\u1ebd c\u00f3 d\u00e0n l\u00f4 nh\u01b0 sau: 67, 12, 65, 13, 69, 18 gh\u00e9p \u0111u\u00f4i gi\u1ea3i \u0111\u1eb7c bi\u1ec7t v\u1edbi \u0111\u1ea7u gi\u1ea3i 7, gh\u00e9p \u0111\u1ea7u gi\u1ea3i \u0111\u1eb7c bi\u1ec7t v\u1edbi \u0111u\u00f4i gi\u1ea3i 7 ch\u00fang ta s\u1ebd c\u00f3 c\u1eb7p s\u1ed1 c\u1ef1c hay \u0111\u1ec3 \u0111\u00e1nh.<\/p>\n
Gh\u00e9p v\u1edbi gi\u1ea3i 6<\/h5>\n
Gi\u1ea3i 6 s\u1ebd c\u00f3 nhi\u1ec1u c\u1eb7p s\u1ed1 h\u01a1n m\u1ed9t ch\u00fat, v\u00ec v\u1eady gh\u00e9p c\u0169ng ra nhi\u1ec1u s\u1ed1 \u0111\u1eb9p h\u01a1n. Ch\u1eb3ng h\u1ea1n \u0111\u1eb7c bi\u1ec7t v\u1ec1 44, gi\u1ea3i 6 v\u1ec1 52 59 01. Ch\u00fang ta s\u1ebd gh\u00e9p \u0111\u01b0\u1ee3c c\u00e1c c\u1eb7p s\u1ed1 sau: 54 42 49 04 41. Nh\u1eefng c\u00e1ch ch\u01a1i n\u00e0y \u0111\u01b0\u1ee3c m\u00ecnh lu\u00e2n phi\u00ean s\u1eed d\u1ee5ng v\u00e0 n\u00f3 c\u00f3 t\u1ef7 l\u1ec7 v\u1ec1 kh\u00e1 cao \u0111\u1ea5y.<\/p>\n