← Abstract Ideas & Symbols · SSC JE Civil

Chapter 1 of 4

Relationship of symbols

In the SSC JE Civil syllabus under Abstract Ideas & Symbols · 2 parts

📑 Contents (12 sections)

Part 1 of 2

Inequalities & Coded Relations

Last reviewed 22 Sept 2026 · 5 min read

The symbols

FormulaThe two rules

Rule 1 — the chain must be unbroken. To compare A and D you need a link at every step: with no gap.

Rule 2 — the arrows must point the same way. gives . But gives nothing between A and C.

And the strictness rule: a chain of signs gives ; if even one link in the chain is strict (), the result is strict ().

So:

Chain Conclusion
nothing
nothing

The either-or case

Two conclusions are an either-or pair when all three of these hold:

  1. they are about the same two terms,
  2. neither follows on its own, and
  3. together they cover every case the chain allows.

The form that almost always appears: the chain proves but not which of the two it is. Then "" and "" each fail alone, and together they are certain — so the answer is either I or II follows.

The other legitimate pair is with (or with ), which exhausts every possibility whatever the chain says.

Coded inequalities

A table defines symbols, for example:

  • P @ Q means
  • P # Q means
  • P & Q means
  • P % Q means
  • P © Q means

Translate every symbol into its inequality first, write the whole chain, then apply the two rules. Never work in the symbols themselves.

Part 2 of 2

Mathematical Operations & Symbol Substitution

Last reviewed 22 Sept 2026 · 5 min read

Substitution questions

A table says, for example: means , means , means , means . Then

is read by replacing each symbol first:

FormulaThe order that never changes

Substitute the symbols, then apply BODMAS: Brackets, Of, Division and Multiplication (left to right), Addition and Subtraction (left to right). The substitution changes the symbols, never the priority rules.

Interchange questions

Two forms appear:

  1. "If and are interchanged, which equation is correct?" — swap those two symbols wherever they appear in each option and test it.
  2. "Interchange which two signs makes the equation correct?" — try each pair in turn; there are only six pairs among four operators, and usually the first or second works.

A third variant swaps two numbers rather than two signs. Test the options rather than solving in general: it is faster.

Balancing an equation

The question gives an equation with blanks and asks which set of signs fills them, such as . Work backwards from the answer: gives no 10; ✓. Test option by option, and remember BODMAS applies to your filled-in version too.

Defined operations

A rule defines a new operator: , or . Substitute the numbers into the definition exactly as written, taking care with the order — most defined operations are not symmetric, so .

For nested expressions, evaluate the innermost bracket first: means find , then apply with 4.

Inserting symbols

"Insert arithmetic signs to make true." Try division first (it constrains most), then multiplication: ✓.

Worked examples

Worked ExampleExample 1 — plain substitution

If means , means , means and means , find .

Solution. Substituting: 64.

Worked ExampleExample 2 — BODMAS after substitution

If means and means , find .

Solution. 14 — division is done before addition even though it was written second.

Worked ExampleExample 3 — which equation is correct

If and are interchanged, which is correct? (a) (b)

Solution. Swapping the two symbols in (a): . In (b): ✓ → (b).

Worked ExampleExample 4 — which signs to interchange

Which two signs should be interchanged to make correct?

Solution. As printed the left side is . Test the pairs:

  • and : ✗
  • and : ✗
  • and : ✓

So and are interchanged. With only three pairs to try among three signs, testing is quicker than reasoning.

Worked ExampleExample 5 — a defined operation

If , find and .

Solution. 22; 4. The operation is not symmetric.

Worked ExampleExample 6 — a nested defined operation

With , find .

Solution. ; then 6.

Worked ExampleExample 7 — inserting signs

Insert signs to make true.

Solution. 5 ✓.

Worked ExampleExample 8 — interchanging numbers

Which two numbers should be interchanged to make correct?

Solution. As printed: ✓ — the equation is already correct, so no interchange is needed. Check the given equation before hunting for a swap.

Worked ExampleExample 9 — mixed symbols

If means , means , means and means , find .

Solution. 18.

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