Finding the Third Proportional to 13,128 and 31,680

Step by Step Solution

1. Step 1: Write the proportion equation
   13,128 : 31,680 = 31,680 : x
2. Step 2: Convert to fraction form
   13,128/31,680 = 31,680/x
3. Step 3: Cross multiply
   13,128x = 31,680 × 31,680
4. Step 4: Simplify right side
   13,128x = 1,003,622,400
5. Step 5: Solve for x
   x = 1,003,622,400/13,128
6. Step 6: Final answer
   x = 76,448.99