Symbols & Notation – MBA CET questions with solutions

Approach: Symbol substitution followed by BODMAS.

Solution:
Replace: × → ÷, − → ×, + → −, ÷ → +.
252 × 9 − 5 + 32 ÷ 92 becomes 252 ÷ 9 × 5 − 32 + 92.
252 ÷ 9 = 28; 28 × 5 = 140.
140 − 32 + 92 = 108 + 92 = 200.

Why the other options are wrong:
A, B, C, E: come from a wrong substitution or from ignoring BODMAS.

Cetking shortcut: Rewrite the whole expression first, then solve; never substitute and calculate at the same time.

Answer: D

Approach: Substitute: × → −, + → ÷, − → ×, ÷ → +, then use BODMAS.

Solution:
15 – 2 ÷ 900 + 90 × 100
→ 15 × 2 + 900 ÷ 90 − 100
= 30 + 10 − 100
= −60.

Why the other options are wrong:
A 190 / B 180: results of doing the operations left to right without BODMAS or swapping signs.
C −90 / D 0: arithmetic slips (e.g. 900 ÷ 90 taken as 0 or 30 dropped).

Cetking shortcut: The statement prints '÷ means ×' and '÷ means +'. Since − already means ×, ÷ must mean + (with ÷ = × the result is 200, not an option).

Answer: E

Approach: Sign interchange: swap the two signs in the equation, then evaluate using BODMAS.

Solution:
Given: 5 + 3 × 8 − 12 ÷ 4 = 3. As written, the left side is 5 + 24 − 3 = 26, so a swap is needed.
Swap − and ÷: 5 + 3 × 8 ÷ 12 − 4.
3 × 8 = 24, then 24 ÷ 12 = 2, so 5 + 2 − 4 = 3. ✔

Why the other options are wrong:
A (+ and −): 5 − 3 × 8 + 12 ÷ 4 = 5 − 24 + 3 = −16.
C (+ and ×): 5 × 3 + 8 − 12 ÷ 4 = 15 + 8 − 3 = 20.
D (÷ and +): 5 ÷ 3 × 8 − 12 + 4 is not a whole number, so it is not 3.
E (× and ÷): 5 + 3 ÷ 8 − 12 × 4 is negative.

Cetking shortcut: The target 3 is small, so the large product 3 × 8 = 24 must be cut down. A swap that puts ÷ next to it does this: 24 ÷ 12 = 2.

Answer: B

Approach: Sign interchange: swap the two signs in the equation, then evaluate using BODMAS.

Solution:
Given: 16 − 8 ÷ 4 + 5 × 2 = 8. As written, the left side is 16 − 2 + 10 = 24, so a swap is needed.
Swap − and ÷: 16 ÷ 8 − 4 + 5 × 2.
16 ÷ 8 = 2 and 5 × 2 = 10, so 2 − 4 + 10 = 8. ✔

Why the other options are wrong:
A (÷ and ×): 16 − 8 × 4 + 5 ÷ 2 = 16 − 32 + 2.5 = −13.5.
D (− and ×): 16 × 8 ÷ 4 + 5 − 2 = 32 + 3 = 35.
C (+ and −) and E (− and +) name the same swap, so they cannot both be right. As printed, this + and − swap also evaluates to 16 + 2 − 10 = 8, so only B is the intended (− and ÷) swap.

Cetking shortcut: Look for a swap that turns the large 16 into a small term (16 ÷ 8 = 2). Here that is − and ÷.

Answer: B

Approach: Sign interchange: swap the two signs in the equation, then evaluate using BODMAS.

Solution:
Given: 9 + 5 ÷ 4 × 3 − 6 = 12.
Swap ÷ and −: 9 + 5 − 4 × 3 ÷ 6.
4 × 3 = 12 and 12 ÷ 6 = 2, so 9 + 5 − 2 = 12. ✔

Why the other options are wrong:
A (+ and ×): 9 × 5 ÷ 4 + 3 − 6 is not a whole number, so it is not 12.
B (÷ and +): 9 ÷ 5 + 4 × 3 − 6 = 1.8 + 12 − 6 = 7.8.
D (+ and −): 9 − 5 ÷ 4 × 3 + 6 = 15 − 3.75 = 11.25.
E (× and −): 9 + 5 ÷ 4 − 3 × 6 = 10.25 − 18, which is negative.

Cetking shortcut: Options whose swap leaves 5 ÷ 4 in place give a fraction, so drop them at once. The answer must move the ÷ away from 5.

Answer: C