Sum and Division example (Python)

Question

>>> sum((1, 2, 3, 4, 5, 6, 7))
28
>>> 28/7
4.0
>>> sum((1,2,3,4,5,6,7,8,9,10,11,12,13,14))
105
>>> 105/7
15.0
>>>

How do I automate this sum and division using a loop maybe?

Edit: Maybe I wasn't clear - I want a loop to keep doing the sum (of multiples of 7, eg 1-7, 1-14, 1-21 etc..) until it reaches x (x is the user input)

Okay, figured it out:

def sum_and_div_of_multiples_of_7(x):
  y = 7
  while (y <= x):
    mof7 = range(1,y)
    print ('mof7 is', mof7)

    total = sum(mof7)
    print ('total =', total)

    div = total/7
    print ('div =', int(div), '\n')

    y = y+7     # increase y

x = 70
sum_and_div_of_multiples_of_7(x)

Solution 1

def sumdiv7(limit):
    for i in range(limit):
        result = sum(range(i*7)) / 7
        print "For", i, ", sumdiv = ", result

Example:

>>> sumdiv7(4)
For 0 , sumdiv =  0
For 1 , sumdiv =  3
For 2 , sumdiv =  13
For 3 , sumdiv =  30

The trick is very simple, you want to sum multiples of 7,

To get the ith multiple of 7, it's just i*7

range is a python function to get a list of numbers from 0 to x

sum sums a list.

Just put these pieces together

Solution 2

The direct answer:

def sum_to_number_divided_by_seven(i):
  return sum(range(i+1)) / 7

The more efficient answer:

def sum_to_number_divided_by_seven(i):
  return (i*(i+1))/14