def add(a, b):
	print "adding %d + %d" % (a, b)
	return a + b

def subtract(a, b):
	print "subtracting %d - %d" % (a, b)
	return a - b

def multiply(a, b):
	print "multiplying %d * %d" % (a, b)
	return a * b

def divide(a, b):
	print "dividing %d / %d" % (a, b)
	return a / b


print "lets do some math with just functions"

age = add(20, 4)
height = subtract(73, 4)
weight = multiply(65, 2)
iq = divide(280, 2)

print "age: %d, height: %d, weight: %d, iq: %d" % (age, height, weight, iq)



#a puzzle for the extra creditm, type it in anyway.
print "heres a puzzle"

what = add(age, subtract(height, multiply(weight, divide(iq, 2))))

print "that becomes: ", what, "can you do it by hand?"