Finding the Third Proportional to 39,120 and 76,280

Step by Step Solution

1. Step 1: Write the proportion equation
   39,120 : 76,280 = 76,280 : x
2. Step 2: Convert to fraction form
   39,120/76,280 = 76,280/x
3. Step 3: Cross multiply
   39,120x = 76,280 × 76,280
4. Step 4: Simplify right side
   39,120x = 5,818,638,400
5. Step 5: Solve for x
   x = 5,818,638,400/39,120
6. Step 6: Final answer
   x = 148,738.20