Solutions to the problem proposed in http://www.theguardian.com/science/alexs-adventures-in-numberland/2015/may/20/can-you-do-the-maths-puzzle-for-vietnamese-eight-year-olds-that-has-stumped-parents-and-teachers

Guardian1

#!/usr/bin/env python
"""
Solutions to the problem proposed in http://gu.com/p/493zk/stw 
"""
from itertools import permutations
from decimal import Decimal

def p(x):
    """
    Define the problem. Follow the canonical order of operations 
    """
    return x[0]+13*x[1]/x[2]+x[3]+12*x[4]-x[5]-11+x[6]*x[7]/x[8]-10

# List of possible values. We will use exact arithmetic to avoid numerical problems.
values = [Decimal(b) for b in range(1,10)]

# The possible solutions are found
sol = [a for a in permutations(values) if (p(a) == Decimal(66))]

print len(sol) # There are 136 possible solutions
for solution in sol:
    print [int(b) for b in solution] # Print the values as integers