Math question :

you should spend no more than 25% of your monthly income on your rent or mortgage.. there is a rule that says your monthly mortgage payment on a apartment is 1% of the original mortgage amount.. what's the largest mortgage a family could afford for their apartment if their family income is $3,000 a month?

sorry it's long : (

you : )

Let x = amount of mortgage (aka the amount by the bank)

25% of the monthly income of $3000 is 0.25*3000 = 750 dollars

So using this rule, the family can pay up to $750 per month on mortgage

1% of the amount loaned (x) is equal to this figure, so

0.01*x = 750
0.01*x/0.01 = 750/0.01
x = 75000

Therefore, the most expensive mortgage this family can afford is $75,000. Anything higher and they go over budget.