Finding the Third Proportional to 9,128.53 and 19,680.47

Step by Step Solution

1. Step 1: Write the proportion equation
   9,128.53 : 19,680.47 = 19,680.47 : x
2. Step 2: Convert to fraction form
   9,128.53/19,680.47 = 19,680.47/x
3. Step 3: Cross multiply
   9,128.53x = 19,680.47 × 19,680.47
4. Step 4: Simplify right side
   9,128.53x = 387,320,850.22
5. Step 5: Solve for x
   x = 387,320,850.22/9,128.53
6. Step 6: Final answer
   x = 42,429.70