Which statements about solving the problem 0.1×5+0.4 are true check all that apply

1. Using a calculator will be much more efficient to solve the problem because there are multiple decimal operations to perform

2. All of the calculators can be done quickly by hand so using a calculator will be less efficient

3. The first calculation cannot be done quickly by hand so using a calculator will be more efficient

4. If a calculator is going to be used it is a good idea to compare it to an estimate of the actual calculation done by hand

5. Using a calculator or solving the problem by hand can both result in the correct answer