If '@' indicates either '+' or '×'; what will be the minimum value of ‘1@2@3@4@5’?
(Note: We have a choice to replace each of the four @ signs in the expression by either '+' or ' ×' operation)

If 'A' means '÷', 'B' means 'x', 'C' means '+' and 'D' means '−', then what will come in place of the question mark (?) in the following equation?
(80 A 8) B 5 C 14 B 2 D 11 B 3 C 72 A4 = ?

If ‘A’ stands for ‘÷’ , ‘B’ stands for ‘x’, ‘C’ stands for ‘+’ and ‘D’ stands for ‘-‘ , what will be come in place of question mark ‘?’ in the following equation?
16 B 4 D 56 A 2 C 7 = ?

If ‘A’ stands for ‘÷’ , ‘B’ stands for ‘x’, ‘C’ stands for ‘+’ and ‘D’ stands for ‘-‘ , what will be come in place of question mark ‘?’ in the following equation?
19 B 3 D 18 A 6 C 5 = ?

What will come in the place of the question mark (?) in the following equation, if ‘+’ and ‘− ’ are interchanged and ‘×’ and ‘÷’ are interchanged?
8 ÷ 5 + 20 × 4 - 9 = ? 

What will come in place of the question mark (?) in the following equation if ‘+’ and ‘−‘ are interchanged and ‘×’ and ‘÷’ are interchanged?
14 ÷ 3 − 15 × 5 + 5 = ?

What will come in the place of the question mark (?) in the following equation, if ‘+’ and ‘−’ are interchanged and ‘×’ and ‘÷’ are interchanged?
66 × 6 ÷ 3 − 128 ÷ 2 + 15 × 3 − 16 ÷ 2 + 17 = ?

What will come in the place of the question mark (?) in the following equation, if ‘+’ and ‘−’ are interchanged and ‘×’ and ‘÷’ are interchanged?
37 ÷ 5 − 91 + 16 × 4 = ?

If ‘+’ means ‘−’, ‘−’ means ‘×’, ‘×’ means ‘÷’ and ‘÷’ means +’, then what will come in place of the question mark (?) in the following equation?
88 − 9 ÷ 195 + 988 × 19 = ?

If ‘A’ stands for ‘÷’ , ‘B’ stands for ‘×’, ‘C’ stands for ‘+’ and ‘D’ stands for ‘-’ , what will come in place of the question mark ‘?’ in the following equation?
9 B 4 D 18 A 9 C 12 = ?

What will come in the place of the question mark (?) in the following equation, if ‘+’ and ‘−’ are interchanged and ‘×’ and ‘÷’ are interchanged?
(84 × 12) ÷ 4 - (72 × 9) ÷ 3 + 15 = ?