To reduce to lowest simplified term, also knows as Lowest Common Denominator (LCD) we just have to find the smallest number that can divide into both numbers. That number is 5. The LCD of [tex]\frac{15}{40}[/tex] is [tex]\frac{3}{8}[/tex]. 5 goes into 15 3 times, and into 40 8 times. So the answer is 3 over 8. Hope that helps!
