Correct Answer - Option 3 : ×, +, ÷, -, =
1) +, ×, -, +, =
Given expression: 15 * 4 * 26 * 2 * 7 * 66
After replacing the * by signs given, we get:
15 + 4 × 26 - 2 + 7 = 66
=> 14 + 104 – 2 + 7 = 66
=> 125 – 2 = 66
=> 123 ≠ 66
2) +, ×, ÷, -, =
Given expression: 15 * 4 * 26 * 2 * 7 * 66
After replacing the * by signs given, we get:
15 + 4 × 26 ÷ 2 - 7 = 66
=> 15 + 52 – 7 = 66
=> 67 – 7 = 66
=> 60 ≠ 66
3) ×, +, ÷, -, =
Given expression: 15 * 4 * 26 * 2 * 7 * 66
After replacing the * by signs given, we get:
15 × 4 + 26 ÷ 2 - 7 = 66
=> 60 + 13 – 7 = 66
=> 73 – 7 = 66
=> 66 = 66
4) ×, +, -, ÷, =
Given expression: 15 * 4 * 26 * 2 * 7 * 66
After replacing the * by signs given, we get:
15 × 4 + 26 - 2 ÷ 7 = 66
=> 60 + 26 – 0.29 = 66
=> 86 – 0.29 = 66
=> 85.71 ≠ 66
Hence, '×, +, ÷, -, =' is the correct answer.