def add(a, b):
    print(f"Adding {a} + {b} = {a+b}")
    return a+b

def subtract(a, b):
    print(f"Substracting {a} - {b} = {a-b}")
    return a-b

def multiply(a, b):
    print(f"Multiplying {a} * {b} = {a*b}")
    return a*b

def divide(a, b):
    print(f"Diving {a} / {b} = {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(f"Testing add: {add(20,5)}")

print(f"Age : {age}, Height : {height}, Weight : {weight}, IQ : {iq}")

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?")
