Finding the Third Proportional to 39,792 and 55,780

Step by Step Solution

1. Step 1: Write the proportion equation
   39,792 : 55,780 = 55,780 : x
2. Step 2: Convert to fraction form
   39,792/55,780 = 55,780/x
3. Step 3: Cross multiply
   39,792x = 55,780 × 55,780
4. Step 4: Simplify right side
   39,792x = 3,111,408,400
5. Step 5: Solve for x
   x = 3,111,408,400/39,792
6. Step 6: Final answer
   x = 78,191.81