Finding the Third Proportional to 128,521.50 and 272,595

Step by Step Solution

1. Step 1: Write the proportion equation
   128,521.50 : 272,595 = 272,595 : x
2. Step 2: Convert to fraction form
   128,521.50/272,595 = 272,595/x
3. Step 3: Cross multiply
   128,521.50x = 272,595 × 272,595
4. Step 4: Simplify right side
   128,521.50x = 74,308,034,025
5. Step 5: Solve for x
   x = 74,308,034,025/128,521.50
6. Step 6: Final answer
   x = 578,175.90