Cabar Minda

条件 = syarat；已知 = diketahui；要找 = dicari 推理题的第一步是把条件一条一条列出来。已知：书 A 是 RM 17；书 B 比 RM 17 多但比 RM 30 少，所以书 B 可能是 RM 18 到 RM 29。马来西亚的纸币有 RM 1、RM 5、RM 10、RM 20、RM 50、RM 100 六种。两张纸币面额一样，而且刚好付清。要找：书 B 的价钱和纸币面额。 例子：“比 RM 17 贵”表示 RM 18 可以，RM 17 不可以。 注意：“lebih mahal”是更贵，不要看反成更便宜。

clue = syarat; given = diketahui; to find = dicari The first step of a puzzle is to list the clues one by one. Given: book A is RM 17; book B is more than RM 17 but less than RM 30, so book B could be anything from RM 18 to RM 29. Malaysian banknotes come in six values: RM 1, RM 5, RM 10, RM 20, RM 50 and RM 100. The two notes have the same value and pay the exact amount. To find: the price of book B and the value of the note. Example: more than RM 17 means RM 18 is allowed but RM 17 itself is not. Watch out: lebih mahal means more expensive; do not read it the other way round.

可能的总值 = jumlah yang mungkin；两倍 = dua kali 两张同面额纸币的总值一定是某个面额的两倍：RM 2、RM 10、RM 20、RM 40、RM 100、RM 200。RM 40 是 RM 20 的两倍，可以。RM 30 要两张 RM 15，RM 60 要两张 RM 30，但没有这种纸币，所以不可能。 例子：两张 RM 50 是 RM 100；两张 RM 5 是 RM 10。 注意：先把所有可能的总值列出来，推理就不会漏掉。

possible totals = jumlah yang mungkin; twice = dua kali Two notes of the same value always make twice one note: RM 2, RM 10, RM 20, RM 40, RM 100 or RM 200. RM 40 is twice RM 20, so it works. RM 30 would need two RM 15 notes and RM 60 would need two RM 30 notes, and no such notes exist. Example: two RM 50 notes make RM 100; two RM 5 notes make RM 10. Watch out: writing down every possible total first makes sure none is missed.

范围 = julat；最少 = paling kurang；最多 = paling banyak 书 B 最少 RM 18，最多 RM 29，所以两本书的总价最少 17 + 18 = RM 35，最多 17 + 29 = RM 46。两张同面额纸币的总值只能是 2、10、20、40、100、200，在 35 到 46 之间的只有 RM 40。所以两本书一共 RM 40，书 B 是 40 − 17 = RM 23，纸币是两张 RM 20。 例子：如果书 A 是 RM 60，B 在 60 到 80 之间，总价 120 到 140，没有符合的两倍面额，就要改条件。 注意：先算出总价的范围，再去对照可能的总值，这样比一个一个猜快。

range = julat; least = paling kurang; most = paling banyak Book B is at least RM 18 and at most RM 29, so the two books together cost at least 17 + 18 = RM 35 and at most 17 + 29 = RM 46. Two notes of the same value can only make 2, 10, 20, 40, 100 or 200, and the only one between 35 and 46 is RM 40. So the two books cost RM 40, book B is 40 − 17 = RM 23, and the notes are two RM 20 notes. Example: if book A were RM 60 and B between 60 and 80, the total would be 120 to 140, and no doubled note fits, so the clues would have to change. Watch out: working out the range of the total first and then comparing it with the possible totals is faster than guessing one price at a time.

求另一本的价钱 = cari harga buku B 两本书一共 RM 40，书 A 是 RM 17，书 B 就是 40 − 17 = RM 23。RM 23 比 RM 17 贵，也少于 RM 30，符合条件。 例子：两样东西共 RM 50，一样是 RM 12，另一样就是 RM 38。 注意：RM 57 是把 40 和 17 加起来，但书 B 是总价的一部分，要用减法。

finding the other price = cari harga buku B The two books cost RM 40 together and book A is RM 17, so book B is 40 − 17 = RM 23. RM 23 is more than RM 17 and less than RM 30, so it fits the clues. Example: two items cost RM 50 together and one is RM 12, so the other is RM 38. Watch out: RM 57 adds 40 and 17, but book B is part of the total, so we must subtract.

验算 = semak；符合 = memenuhi 推理题的最后一步是把答案代回每一个条件。书 B 比 A 贵：23 > 17，对。书 B 少于 RM 30：23 < 30，对。两本书的总价：17 + 23 = 40。两张纸币：20 + 20 = 40，跟总价一样，刚好付清。四个条件都符合，答案 RM 23 和两张 RM 20 就是对的。 例子：如果算出书 B 是 RM 33，33 < 30 不成立，就知道算错了。 注意：只要有一个条件不符合，答案就要重新找。

checking = semak; satisfies = memenuhi The last step of a puzzle is to put the answer back into every clue. Book B costs more than A: 23 > 17, true. Book B is under RM 30: 23 < 30, true. The two books together: 17 + 23 = 40. The two notes: 20 + 20 = 40, the same as the total, so the payment is exact. All four clues hold, so RM 23 and two RM 20 notes is the right answer. Example: if book B had come out as RM 33, the test 33 < 30 would fail and we would know something went wrong. Watch out: if even one clue fails, the answer has to be worked out again.