यदि 28 A 49 B 77 C 11 = -14 और 30 A 50 B 88 C 22 = -16 है, तो 85 A 15 B 40 C 8 = ?

If '+' is interchanged with '-' and '×' is interchanged with '÷', what will come in place of '?' in the following equation? 529 ÷ 23 + 89 - 12 × 9 = ?

By interchanging which two signs will the given equation become correct? 15 - 9 ÷ 6 × 10 + 5 = 25