C :: Float Variables Not Able To Be Multiplied With Each Other

why does the 2 variables, loanAmt and intRatem not work when they are multiplied together. The question is " Write a program that calculates the remaining balance on a loan after the first, second and third monthly payments. "

Code:

#include <stdio.h>
void a5()
{
float loanAmt, intRate, intRatem, dintRate, payment, pay1, pay2, pay3,test;
printf("Enter amount of loan:");
scanf("%f", &loanAmt);
}

[code].....