Finding the Third Proportional to 133,611 and 278,239.50

Step by Step Solution

1. Step 1: Write the proportion equation
   133,611 : 278,239.50 = 278,239.50 : x
2. Step 2: Convert to fraction form
   133,611/278,239.50 = 278,239.50/x
3. Step 3: Cross multiply
   133,611x = 278,239.50 × 278,239.50
4. Step 4: Simplify right side
   133,611x = 77,417,219,360.25
5. Step 5: Solve for x
   x = 77,417,219,360.25/133,611
6. Step 6: Final answer
   x = 579,422.50