Let's Convert in this way:

1. To convert inch into centimeter, multiply by 5 and then divide by 2.
2. To convert cm. into inch, multiply by 2 and then divide by 5.
3. To convert pound into kg, multiply by 11 and then divide by 5.
4. To convert kg. into pound, multiply by 5 and then divide by 11.
5. To convert litre into gallon, multiply by 50 and then divide by 11.
6. To convert gallon into litre, multiply by 11 and then divide by 50.
7. To convert celsius into fahrenheit, multiply by 9, divide by 5 and add 32 at last.
8. To convert fahrenheit into celsius, subtract 32, multiply by 5 and divide by 9 at last.