Temperature value from centigrade to Fahrenheit prrogram in c

#include<stdio.h>
void main()
{
float cen,fah;
printf("Enter temperature in  centigrade scale:");
scanf("%f",&cen);

fah=9/5.0*cen+32;

printf("Equivalent Fahrenheit scale value is %f",fah);

}


OUTPUT:

Enter temperature in  centigrade scale: 27.5

Equivalent Fahrenheit scale value is 81.5