Mathematical Operations – Railway Reasoning (part – 3)

Total Questions: 50

11. If ‘×’ means -, ‘-‘means ’÷’, ‘÷’means ” +’’ , ” +’’ means ‘×’, what will come in place of the question mark (?) in the following equation? [Group - D 06/10/2022 (Afternoon)]

27 ÷ 288 + 2× 2 × 22 − 2=?

Correct Answer: (c) 590
Solution:

27 ÷ 288 + 2 × 2 × 22 − 2 = ?
According to the question,
27 + 288 × 2 − 2 − 22 ÷ 2
⇒ 27 + 576 − 2 − 11 = 590

12. If ‘+’ means ’ ’ , means +, ‘÷ ’ × − × means ‘÷ ’ , and ‘ ’ means, ‘− ’ what will come in place of the question mark (?) in the following equation? [Group - D 06/10/2022 (Afternoon)]

4 + 22 × 2÷ 4 − 9 ?

Correct Answer: (a) 49
Solution:

4 + 22 × 2 ÷ 4 − 9 = ?
According to the above equation,
4 × 22 ÷ 2 − 4 + 9 ⇒ 4 × 11 − 4 + 9 = 49

13. Which two numbers from amongst the given options should be interchanged to make the given equation correct? [Group - D 07/10/2022 (Morning)]

382 + 9 ÷ 4 − 39 × 172 = 74

Correct Answer: (d) 9 and 172
Solution:

382 + 9 ÷ 4 − 39 × 172 = 74
By hit and trial method, Go through option (d)
382 + 172 ÷ 4 − 39 × 9 = 74
⇒ 382 + 43 − 351 = 74 ⇒ 74 = 74 (satisfy)

14. What will come in the place of "?" in the following equation, if "+" and "−" are interchanged and also × and ÷ are interchanged? [Group - D 07/10/2022 (Morning)]

100 × 25 − 10 ÷ 5 + 24 = ?

Correct Answer: (c) 30
Solution:

100 × 25 – 10 ÷ 5 + 24 = ?
According to question,
100 ÷ 25 + 10 × 5 - 24 = ?
⇒ 4 + 50 - 24 = 30

15. If ‘+’ means ‘−’, ‘−’ means ‘×’, ‘×’ means ‘÷’, ‘÷’ means ‘+’ in the following equation what will come in place of the question mark (?) [Group - D 07/10/2022 (Afternoon)]

102 ÷ 15 × 5 − 7 + 10 × 2 = ?

Correct Answer: (c) 118
Solution:

102 ÷ 15 × 5 – 7 +10 × 2 = ?
According to question,
102 + 15 ÷ 5 × 7 - 10 ÷ 2
⇒ 102 + 3 × 7 - 5 ⇒ 102 + 21 - 5 = 118

16. If ‘+’ mean ‘÷’, ‘÷’ mean ‘+’, ‘−’ means ‘×’, ‘×’ mean ‘−’, what will come in place of the question mark (?) in the following equation ? [Group - D 07/10/2022 (Evening)]

32 + 16 ÷ 24 − 8 × 180 = ?

Correct Answer: (d) 14
Solution:

32 + 16 ÷ 24 – 8 × 180 = ?
According to question,
32 ÷ 16 + 24 × 8 - 180
⇒ 2 + 192 - 180 = 14

17. If ‘+’ means ‘×’, ‘−’ means ‘÷’, ‘×’ means ‘−’ and ÷ means +, what will come in place of the question mark (?) in the following equation? [Group - D 11/10/2022 (Morning)]

9 + 7 ÷ 8 − 4 × 2 = ?

Correct Answer: (a) 63
Solution:

9 + 7 ÷ 8 – 4 × 2
According to the question,
9 × 7 + 8 ÷ 4 - 2 ⇒ 63 + 2 - 2 = 63

18. If + means ‘÷’, − means ‘+’, ‘×’ means ‘−’ and ÷ means ×, what will be the value of the following expression? [Group - D 11/10/2022 (Afternoon)]

[{(16 × 6) − (2 ÷ 3)} + (4 − 4)] ÷ 2

Correct Answer: (c) 4
Solution:

[{(16 × 6) – (2 ÷ 3)} + (4 – 4)] ÷ 2
According to question,
[{(16 - 6) + (2 × 3)} ÷ (4 + 4)] × 2
[{10 + 6} ÷ 8] × 2 = 4

19. If ‘+’ means ‘−’, ‘−’ means ‘÷’, ‘×’ means ‘+’ and ÷ means ‘×’ what will be the value of the following expression? [Group - D 11/10/2022 (Evening)]

[{(6 × 9) + (3 ÷ 2)} − (7 + 4)] ÷ 2

Correct Answer: (a) 6
Solution:

[{(6 × 9) + (3 ÷ 2)} – (7 + 4)] ÷ 2
According to question,
[{(6 + 9) - (3 × 2)} ÷ (7 - 4)] × 2
⇒ [{(15) - (6)} ÷ (3)] × 2 ⇒ [3 × 2] = 6

20. Which two signs should be interchanged to make the following equation correct? [Level 6 (09/05/2022) Shift 1]

4 ÷ 8 + 5 − 6 × 2 = 34

Correct Answer: (b) ÷, ×
Solution:

In these type of questions, we will check through options one by one, and on doing so option (b) gets satisfied.
4 ÷ 8 + 5 – 6 × 2 = 34
Putting option (b) in above equation, we get
4 × 8 + 5 – 6 ÷ 2
= 4 × 8 + 5 – 3 = 32 + 5 – 3 = 34 = RHS