Before going to the program first let us see how to convert Celsius to Fahrenheit?

To convert from Celsius to Fahrenheit: first **multiply by 180/100**, then **add 32.**

But **180/100** can be simplified to **9/5**, so this is the easiest way:

**°C to °F: Multiply by 9, then divide by 5, then add 32**

So now we can write a formula like this:

**Celsius to Fahrenheit: (°C × ^{9}/_{5}) + 32 = °F**

**Other Method: ****Use 1.8 instead of 9/5**

**9/5** is equal to **1.8**, so we can also use this method.

**Thus the formula is:**

**Celsius to Fahrenheit: °C × 1.8 + 32 = °F**

**Example:** Convert 41° Celsius to Fahrenheit

*First:* 41° × 1.8 = 73.8*Then:* 73.8 + 32 = **105.8° F**

## Program code to convert Celsius to Fahrenheit in C:

#include<stdio.h> #include<conio.h> void main() { float cels,fah; clrscr(); printf("Enter the temperature in Celsius:"); scanf("%f",&cels); fah=(1.8*cels)+32; printf("nConverted Temperature is %.2f%cF",fah,248); getch(); }

## Explanation:

- First the computer reads the temperature in Celsius from the user and stores it in the “cels” variable using the following lines:

printf("Enter the temperature in Celsius:"); scanf("%f",&cels);

**Note:** **%f** is used to read the **floating-point value (decimal value).**

- Then using the formula the Fahrenheit value is calculated and stored in the “fah” variable using the following line:

fah=(1.8*cels)+32;

- Finally the Fahrenheit value is printed on the screen using the following line:

printf("nConverted Temperature is %.2f%cF",fah,248);

**Note:** **%.2f** is used to print the floating-point value with only **2 decimal places,**

**%c** is used to print a **character** and

**248 **is the ASCII value of the character **” º “(degree)**.