80x86 Assembly div instruction with WeightedAvg

COMMENT @
Objective:	Prompt and allocate DWORD(32 bits) size labels for Grade1-Grade4 and Weight1-Weight4.
			Solve for WeightedSum = G1*W1 + G2*W2 + G3*W3 + G4*W4
			Solve for SumOfWeights = W1 + W2 + W3 + W4
			Solve for WeightedAverage = (WeightedSum/SumOfWeights)
			Display WeightedAverage & WeightedSum
@

; Preprocessor directives
.586		; use the 80586 set of instructions
.MODEL FLAT	; use the flat memory model (only 32 bit addresses, no segment:offset)

; External source files
INCLUDE io.h   ; header file for input/output

; Stack configuration
.STACK 4096	   ; allocate 4096 bytes for the stack

; Named memory allocation and initialization
.DATA
Grade1			DWORD		?
Grade2			DWORD		?
Grade3			DWORD		?
Grade4			DWORD		?

Weight1			DWORD		?
Weight2			DWORD		?
Weight3			DWORD		?
Weight4			DWORD		?

WeightedSum		DWORD		?
WeightedAvg		DWORD		?
SumOfWeight		DWORD		?
WeightAvg		BYTE		32 DUP (?)
WeightSum		BYTE		32 DUP (?)

;Prompt the user for input reserving a single byte for each prompt
prompt1		BYTE		"Enter value for Grade1: ", 0
prompt1b	BYTE		"Enter value for Weight1: ", 0

prompt2		BYTE		"Enter value for Grade2: ", 0
prompt2b	BYTE		"Enter value for Weight2: ", 0

prompt3  	BYTE		"Enter value for Grade3: ", 0
prompt3b 	BYTE		"Enter value for Weight3: ", 0

prompt4		BYTE		"Enter value for Grade4: ", 0
prompt4b 	BYTE		"Enter value for Weight4: ", 0

;Create a label of byte size and duplicate it x40. This will hold our Grades and Weights
value		BYTE		40 DUP (?)

;Final prompt for output
sumPrompt	BYTE		"Weighted Sum: ", 0
avgPrompt	BYTE		"Weighted Average: ", 0



; procedure definitions
.CODE
_MainProc PROC

;Ask for Grade1 and Weight1 *REPEAT FOR GRADE1-4 & WEIGHT1-4*
	input	prompt1, value, 40		;Ask for Grade1 input
	atod	value
	mov		Grade1, eax

	input	prompt1b, value, 40		;Ask for Weight1 input
	atod	value
	mov		Weight1, eax

	input	prompt2, value, 40		;Ask for Grade2 input
	atod	value
	mov		Grade2, eax
	input	prompt2b, value, 40		;Ask for Weight2 input
	atod	value
	mov		Weight2, eax

	input	prompt3, value, 40		;Ask for Grade3 Input
	atod	value
	mov		Grade3, eax

	input	prompt3b, value, 40		;Ask for Weight3 input
	atod	value
	mov		Weight3, eax

	input	prompt4, value, 40		;Ask for Grade4 Input
	atod	value
	mov		Grade4, eax

	input	prompt4b, value, 40		;Ask for Weight4 input
	atod	value
	mov		Weight4, eax


	mov		eax, 0
	mov		ecx, Weight1
		;WeightedSumPart1
		G1:
			add		eax, Grade1
			dec		ecx;
			jnz		G1

		;WeightedSumPart2
			mov		ebx, 0
			mov		ecx, Weight2
		G2:
			add		ebx, Grade2
			dec		ecx
			jnz		G2
			add		eax, ebx

		;WeightedSumPart3
			mov		ebx, 0
			mov		ecx, Weight3
		G3:
			add		ebx, Grade3
			dec		ecx

			jnz		G3

			add		eax, ebx
		;WeightedSumpart4
			mov		ebx, 0
			mov		ecx, Weight4

		G4:
			add		ebx, Grade4
			dec		ecx
			jnz		G4
			add		eax, ebx
			mov		WeightedSum, eax
SumOfWeights:
	;Remember: SumOfWeights(EBX) = Weight1 + Weight2 + Weight3 + Weight4
	mov		ebx, 0
	add		ebx, Weight1
	add		ebx, Weight2
	add		ebx, Weight3
	add		ebx, Weight4


	mov		SumOfWeight, ebx

	dtoa	WeightSum, WeightedSum
WeightedAverage:
	mov		eax, SumOfWeight
	div		WeightSum
	dtoa	WeightAvg, eax
	output	sumPrompt, WeightSum
	output	avgPrompt, WeightAvg
        mov     eax, 0  ; exit with return code 0

        ret
_MainProc ENDP

END   ; end of source code

COMMENT @
Grades:		Weights:
88		1
77		2
94		1
85		3
SumOfWeight = 7
WeightedSum = 591
WeightedAvg = 81	;Displays different

@