diff --git a/02-vars-and-math.c b/02-vars-and-math.c
new file mode 100644
index 0000000..bd7f578
--- /dev/null
+++ b/02-vars-and-math.c
@@ -0,0 +1,20 @@
+#include <stdio.h>
+
+/* print Fahrenheit-Celsius table
+	for fahr = 0, 20, ..., 300 */
+int main()
+{
+	int fahr, celsius;
+	int lower, upper, step;
+
+	lower = 0;
+	upper = 300;
+	step = 20;
+
+	fahr = lower;
+	while (fahr <= upper) {
+		celsius = 5 * (fahr-32) / 9;
+		printf("%d\t%d\n", fahr, celsius);
+		fahr = fahr + step;
+	}
+}
diff --git a/Makefile b/Makefile
index 268703a..89ef3b6 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,7 @@
-all: hello
+all: hello mathvars
 
 hello: 01-hello-world.c
 	gcc -o ./bin/01-helloworld 01-hello-world.c
+
+mathvars: 02-vars-and-math.c
+	gcc -o ./bin/02-mathvars 02-vars-and-math.c