Answer:
[tex]\[q1 + 2q2+3q3+4q4\] [/tex]
[tex]\[4q1 + 3q2+2q3+q4\] [/tex]
Step-by-step explanation:
Quantity of good1 = q1
Unit price of good1 = $1
Quantity of good2 = q2
Unit price of good2 = $2
Quantity of good3 = q3
Unit price of good3 = $3
Quantity of good4 = q4
Unit price of good4 = $4
Total expenditure = [tex]\[\sum (quantity*unitprice)\][/tex]
= [tex]\[q1 + 2q2+3q3+4q4\] [/tex]
If the prices change to $4, $3, $2 and $1 per unit respectively, total expenditure = [tex]\[4q1 + 3q2+2q3+q4\] [/tex]