Free practice · numeric · medium

Practice

Calculate a workplace line total

A line item has unit_price = 12.5, quantity = 4, and discount = 5. What is unit_price * quantity - discount?

Typed expression trace

Every value has a type before an operator uses it

Source
Raw value and its current type
Contract
Allowed type, format, and range
Conversion
Explicit and failure-aware
Expression
Operators applied by precedence
Evidence
Resulting value and type

Track the source value, current type, conversion boundary, evaluation order, and resulting type instead of relying on how a value looks.