Who needs Windows Calc? Cortana can do simple math, and with one extra keystroke you can display a full-featured calculator in the Start menu.
By Ed Bott for The Ed Bott Report | February 24, 2016 -- 12:27 GMT (12:27 GMT) | Topic: Windows 10

You don't need an app to do basic math in Windows 10. If you've enabled Cortana, you can perform those calculations by tapping the Windows key and then typing the formula in the search box.

Make your formula as simple or as complex as you want, using standard operators: + and - for addition and subtraction, * and / for multiplication, % for percentages, ^ for exponentiation. Cortana automatically groups internal calculations; use parentheses if you want to control grouping.

As soon as you type an equals sign or press Enter, Cortana displays the result at the top of the search results list.

Want to do more calculations using the result of that formula? Press Enter to open the full calculator shown here.

Note that the calculator vanishes as soon as you click away, and you can't copy the formula or its results.

Windows 10 tip: How to access Cortana's secret calculator | ZDNet