Reasoning topic
A code turns a word into something else by a fixed rule. Find the rule from the example you are given, letter by letter, then use it on the new word.
A typical question gives two words with their codes and asks you to code a third word by the same rule.
If PALE is coded as 7865 and EARTH is coded as 58432, how is the following word coded? HEART
25843
From the two codes, H = 2, E = 5, A = 8, R = 4 and T = 3, so HEART is 25843.
Write the word over its code and compare them letter by letter.
Name what each letter does: moves some places in the alphabet, changes position in the word, is replaced by a fixed letter, digit or word, or becomes a number worked out from its position.
Check the rule on every letter of the example. Then apply it to the new word.
In a certain code language, 'M5T9' is written as 'L5S9' and 'F2K7' is written as 'E2J7'. How will 'K2P7' be written in that code?
Answer: J2O7
1. In a language, 'water' is called 'juice', 'goat' is called 'sheep', 'buffalo' is called 'goat', 'milk' is called 'water', and 'cow' is called 'buffalo'. In this language, what does a cow give?
Answer the plain question first, then put it in code.
water
A cow gives milk, and in this language milk is called 'water'.
2. In a certain code the letters of a word are swapped in neighbouring pairs (1st with 2nd, 3rd with 4th, and so on) and then each letter is moved one step forward. How is 'MARKET' written in this code?
Do the two steps in the order given: swap the pairs first, then move each letter.
BNLSUF
Swap the pairs: MA → AM, RK → KR, ET → TE, so MARKET becomes AMKRTE. Move each letter one step forward: A → B, M → N, K → L, R → S, T → U, E → F. The code is BNLSUF.
3. In a certain coded language, the code of A is 2 (i.e. 1 × 2), B is 6 (i.e. 2 × 3), C is 12 (i.e. 3 × 4) and so on. What is the code of OUT?
Find each letter’s position in the alphabet first.
240462420
A letter in place n is coded n × (n + 1). O is 15th: 15 × 16 = 240. U is 21st: 21 × 22 = 462. T is 20th: 20 × 21 = 420. So OUT is 240462420.
Practise Coding-Decoding in the app. The questions follow your level, and what you practise comes back just before you'd forget it.
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