Question

a textbook store sold a combined total of 404 psychology and sociology textbooks in a week. the number of sociology textbooks sold was 86 less than the number of psychology textbooks sold. how many textbooks of each type were sold?
number of psychology textbooks sold:
number of sociology textbooks sold:

Explanation:

Step1: Define variables

Let \( x \) be the number of psychology textbooks sold. Then the number of sociology textbooks sold is \( x - 86 \).

Step2: Set up equation

The total number of textbooks sold is the sum of psychology and sociology textbooks, so \( x+(x - 86)=404 \).

Step3: Solve the equation

Simplify the left side: \( 2x-86 = 404 \).
Add 86 to both sides: \( 2x=404 + 86=490 \).
Divide both sides by 2: \( x=\frac{490}{2}=245 \).

Step4: Find sociology textbooks

The number of sociology textbooks is \( x - 86=245-86 = 159 \).

Answer:

Number of psychology textbooks sold: \( 245 \)
Number of sociology textbooks sold: \( 159 \)