Finding the Third Proportional to 10,109.25 and 20,720.25

Step by Step Solution

1. Step 1: Write the proportion equation
   10,109.25 : 20,720.25 = 20,720.25 : x
2. Step 2: Convert to fraction form
   10,109.25/20,720.25 = 20,720.25/x
3. Step 3: Cross multiply
   10,109.25x = 20,720.25 × 20,720.25
4. Step 4: Simplify right side
   10,109.25x = 429,328,760.06
5. Step 5: Solve for x
   x = 429,328,760.06/10,109.25
6. Step 6: Final answer
   x = 42,468.90