Which two numbers should be interchanged to make the given equation correct? (21 4+(84 7) 2-15 5+42=105 ) (Note: Interchange should be done of entire number and not individual digits of a given number.)

Step-by-step solution

Given equation: (21 4+(84 7) 2-15 5+42=105 ) Let's check each option one by one. Option 1) 4 and 2 Given: (21 4+(84 7) 2-15 5+42=105 ) After interchanging the numbers we get; ( aligned & 21 2+(84 7) 4-15 5+42=105 & 42+12 4-15 5+42=105 & 42+48-75+42=105 & 132-75=105 & 57 105 aligned ) Option 2) 84 and 42 Given: (21 4+(84 7) 2-15 5+42=105 ) After interchanging the numbers we get; ( aligned & 21 4+(42 7) 2-15 5+84=105 & 21 4+6 2-15 5+84=105 & 84+12-75+84=105 & 180-75=105 & 1 0 5 = 1 0 5 aligned ) Option 3) 4 and 5 Giv