Add sales tax example

07_04_sales_tax.c

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+/*
+ * =====================================================================================
+ *
+ *       Filename:  07_04_sales_tax.c
+ *
+ *    Description:  Exercise 7.4
+ *                  Write a program to add an 8% sales tax to a given amount
+ *                  and round the result to the nearest penny.
+ *
+ *        Version:  1.0
+ *        Created:  09/18/2011
+ *       Revision:  none
+ *       Compiler:  gcc
+ *
+ *         Author:  Zach Williams, hey AT zachwill DOT com
+ *
+ * =====================================================================================
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+
+float add_sales_tax(float original) {
+    float tax = 1.08, total;
+    total = original * tax;
+    return total;
+}
+
+
+int main(int argc, const char *argv[]) {
+    float input, total_amount;
+    input = atof(argv[1]);
+    total_amount = add_sales_tax(input);
+    printf("Price:  %.2f\n", input);
+    printf("Total:  %.2f\n", total_amount);
+    return 0;
+}