It is very important to check your answers using an inverse operation.
You can use a calculator.
Remember that....
Adding and subtracting are inverses.
Multiplying and dividing are inverses.
Example 1
594 - 26 = 568
Check by doing
568 + 26 = 594
Example 2
41820 ÷ 85 = 492
Check by doing
492 × 85 = 41820