In the following question, by using which mathematical operators will the expression become correct?
1 14 30 20 10 = 121) 1 ÷ 14 × 30 - 20 + 10 = - 7.85 ≠ 12
2) 1 + 14 × 30 ÷ 20 - 10 = 12
3) 1 ÷ 14 - 30 + 20 × 10 = 170.071 ≠ 12
4) 1 × 14 ÷ 30 + 20 - 10 = 10.46 ≠ 12
Hence, ‘+ × ÷ -’ is the correct answer.