20•5-63

The expression 20•5-63 can be simplified using the order of operations (PEMDAS/BODMAS) which states that multiplication and division should be done before addition and subtraction.

Following this rule, we first solve 20 times 5:

20 • 5 = 100

Now we subtract 63 from the result:

100 - 63 = 37

Therefore, 20•5-63 equals 37.