Which two signs should be interchanged to make the below equation mathematically correct?

64 - 16 × 25 ÷ 80 + 10 = 59 

Given statement : 64 - 16 × 25 ÷ 80 + 10 = 59 

According to the question, after interchanging the signs:

So,

• Option - (1) : ÷ and -​

Given statement : 64 - 16 × 25 ÷ 80 + 10 = 59 

After interchanging

64 ÷ 16 × 25 - 80 + 10 = 59

4 × 25 - 80 + 10 = 59 

100 +10 - 80 = 59

110 - 80 = 59

30 ≠ 59 (LHS ≠ RHS)

• Option - (2) : ÷ and x

Given statement : 64 - 16 × 25 ÷ 80 + 10 = 59 

After interchanging:

64 - 16 ÷ 25 × 80 + 10 = 59 

64 - 0.64 × 80 + 10 = 59

64 + 10 - 51.2 = 59

74 - 51.2 = 59

-22.8 ≠ 59 (LHS ≠ RHS)

• Option - (3) : - and +

Given statement : 64 - 16 × 25 ÷ 80 + 10 = 59 

After interchanging:

64 + 16 × 25 ÷ 80 - 10 = 59 

64 + 16 × 0.3125 - 10 = 59

64 + 5 - 10 = 59

69 - 10 = 59

59 = 59 (LHS = RHS)

• Option - (4) : × and -

Given statement : 64 - 16 × 25 ÷ 80 + 10 = 59 

After interchanging:

64 × 16 - 25 ÷ 80 + 10 = 59 

64 × 16 - 0.3125 + 10 = 59

1024 + 10 - 0.3125 = 59

1034 - 0.3125 = 59

1033.6875 ≠ 59 (LHS ≠ RHS)

Hence, "Option - (3)" is the correct answer.