Final answer:
The Jacksons have 5/12 of their total monthly income remaining for their expenses each month.
Step-by-step explanation:
To find out what fraction of the Jacksons' money remains for their expenses each month, we need to subtract the fractions spent on rent and food from 1 (since the total income is represented as 1 whole).
The fraction spent on rent is 1/3, and the fraction spent on food is 1/4.
So, the fraction of their money remaining for expenses is:
1 - 1/3 - 1/4 = 12/12 - 4/12 - 3/12 = 5/12
Therefore, 5/12 of their money remains for their expenses each month.