ex21.py

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 "Let's do some math with just functions!"

age = add(30,5)
height = subtract(78,4)
weight = multiply(90,2)
iq = divide(100,2)

print "Age: %d,Height: %d,Weight: %d,IQ: %d" % (age,height,weight,iq)

#A puzzle for the extra credit,type it in anyway.
print "Here is a puzzle."

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

print "That becomes: ", what, "Can you do it by hand?"