
Doug C. answered 10/26/22
Math Tutor with Reputation to make difficult concepts understandable
Try this for starters:
Ads
Bills
Letters
Magazines
Let the variables A, B, L, M represent the number of each.
Then:
A + B + L + M = 27 I(pieces of mail received by Jones family)
B = L + 3 (bills is 3 more then letters)
A = B + 5 (ads is 5 more then bills)
M = L (magazines is same number as letters).
We want the number of magazines, but looks like most everything is in terms of L. If we solve for L first, then M will be the same value.
Try replacing all letters in the 1st equation with expressions in terms of L.
A + B + L + L = 27 (M=L)
A + (L + 3) + L + L = 27 (B = L+3)
(B + 5) + L + 3 + L + L = 27 (A = B+5)
((L + 3) +5) + L + 3 + L + L = 27 (B = L+3)
So what we have is:
L + 3 + 5 + L + 3 + L + L = 27
4L + 11 = 27.
Take if from there solving for L. And since M = L, that will be the answer to the question.
As a check determine the values of A and B too, add the results to make sure they combine to 27.