If the symbols +, −, ×, ÷, >, =, < respectively denote addition, subtraction,…

2015

If the symbols +, −, ×, ÷, >, =, < respectively denote addition, subtraction, multiplication, division, greater than, equal to, less than; then which of the following relation is correct?

  1. A.

    {(5 × 3 + 7) ÷ 8} > (4 × 2)

  2. B.

    (5 + 3) < (7 − 8 × 4 + 2)

  3. C.

    5 < 3 > (7 − 8) > (4 + 2)

  4. D.

    (5 + 2 × 1) = (3 + 4) > 1

Show answer & explanation

Correct answer: D

Evaluating an arithmetic relation follows a fixed order of operations (BODMAS/VBODMAS): simplify inside brackets first, then carry out multiplication and division from left to right, then addition and subtraction from left to right. When an option chains more than one comparison symbol, such as A related to B related to C, the whole statement holds only if every adjacent pair in the chain satisfies its own stated relation — one failing link breaks the entire chain.

  1. {(5 × 3 + 7) ÷ 8} compared with (4 × 2): on the left, 5 × 3 = 15, then 15 + 7 = 22, then 22 ÷ 8 = 2.75; on the right, 4 × 2 = 8. This option compares 2.75 with 8 under the '>' symbol.

  2. (5 + 3) compared with (7 − 8 × 4 + 2): the left side gives 5 + 3 = 8; on the right, multiplication is carried out before addition and subtraction, so 8 × 4 = 32, then 7 − 32 = −25, then −25 + 2 = −23. This option compares 8 with −23 under the '<' symbol.

  3. 5 compared with 3 compared with (7 − 8) compared with (4 + 2): reducing the brackets gives (7 − 8) = −1 and (4 + 2) = 6, so the chain to examine becomes 5, then 3, then −1, then 6, linked in sequence by the '<', '>', '>' symbols shown, and every one of these three links must hold for the option to be true.

  4. (5 + 2 × 1) compared with (3 + 4) compared with 1: on the left, multiplication is carried out first, so 2 × 1 = 2, then 5 + 2 = 7; the middle expression (3 + 4) also gives 7; the final value shown is 1. This option chains two comparisons — the left value against the middle value under '=', and the middle value against 1 under '>'.

Checking each reduced pair against its own symbol: 2.75 is not greater than 8, so that relation fails; 8 is not less than −23, so that relation fails; the very first link, 5 compared with 3, already fails under '<', so the whole chain fails regardless of the remaining links. In the relation (5 + 2 × 1) = (3 + 4) > 1, however, 7 equals 7, confirming the first link, and 7 is indeed greater than 1, confirming the second link — an independent recheck by substituting the numbers back into each bracket (2 × 1 = 2, so 5 + 2 = 7; 3 + 4 = 7) reproduces the same equality.

Every link in the chain (5 + 2 × 1) = (3 + 4) > 1 is satisfied, making it the only correct relation among the four given in this item.

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