### Design Recipe One - Program Definitions

 CONTRACT, PURPOSE, HEADER - Name of program, Input / Output EXAMPLES - Function Calls (2 or more) with the estimated answer that YOU calculate. BODY - Formula to calculate the answer using variable parameters in the header TEST - Execute the program. Compare the computer answer to your estimate. Check logic.

#### SALARYGross Wages - Taxes = Net Pay

 ```;;wage: number number -> number ;;compute weekly wage given the number hours worked and the hourly rate (define (wage hours hrRate) ``` ```(wage 20 10) = 200 (wage 40 10) = 400 (wage 5 47.25) = 250 ``` ``` (* hours hrRate) ``` Interaction Window: ```200 = 200 400 = 400 #i236.25 = 250 ``` Definition Window: ```;;wage: number number -> number ;;compute weekly wage given the number hours worked and the hourly rate (define (wage hours hrRate) (* hours hrRate)) (wage 20 10) = 200 (wage 40 10) = 400 (wage 5 47.25) = 250 ```

 ```;;tax: number -> number ;;compute taxes taken out of a paycheck at a tax rate of 15% (define TAXRATE .15) (define (tax wages) ``` ```(tax 200) = 30 (tax 400) = 60 (tax 236.25) = 36 ``` ``` (* wages TAXRATE) ``` Interaction Window: ```#i30.0 = 30 #i60.0 = 60 #i35.4375 = 36 ``` Definition Window: ```;;tax: number -> number ;;compute taxes taken out of a paycheck at a tax rate of 15% (define TAXRATE .15) (define (tax wages) (* wages TAXRATE)) (tax 200) = 30 (tax 400) = 60 (tax 236.25) = 36 ```

 ```;; taxed-wage : number -> number ;; computes the taxed-wage, given the number of hours worked (define (taxed-wage hours hrRate) ``` ```(taxed-wage 20 10) = 170 (taxed-wage 40 10) = 340 (taxed-wage 5 47.25) = 200 ``` ``` (- (wage hours hrRate) (tax (wage hours hrRate)) ``` Interaction Window: ```Welcome to DrScheme, version 100. Language: Beginner. #i170.0 = 170 #i340.0 = 340 #i200.8125 = 200 ``` Definition Window: ```(define (wage hours hrRate) (* hours hrRate)) (define TAXRATE .15) (define (tax wages) (* wages TAXRATE)) ;; taxed-wage : number -> number ;; computes the taxed-wage, given the number of hours worked (define (taxed-wage hours hrRate) (- (wage hours hrRate) (tax (wage hours hrRate)))) (taxed-wage 20 10) = 170 (taxed-wage 40 10) = 340 (taxed-wage 5 47.25) = 200 ```