Answer to Question #214848 in Combinatorics | Number Theory for Lebza

Question

Explain with illustrations how you would use rounding off and compensation as calculation techniques to judge the reasonableness of solutions. Give one example in each case.

Answer 1

reasonableness can be achieved through checking to verify that the result of the solution or the calculation of the problem is correct or not, be either estimating or by plugging in your result to check it. A reasonable estimate does not exceed the original numbers in a problem. 

For instance, in a division problem like 424 ÷ 4 − 10, we can check is our answer is reasonable or not, by estimating an approximate answer or by plugging in using the division formula. 

We can round down 424 to the nearest hundreds, to estimate the answer. Since 96 (actual answer) ≈ 90 (estimate answer), we know our solution is correct.

We can check our solution by plugging in to verify using, 96 × 4 + 10 as well.