Finding the Third Proportional to 145,231.50 and 316,300.50

Step by Step Solution

1. Step 1: Write the proportion equation
   145,231.50 : 316,300.50 = 316,300.50 : x
2. Step 2: Convert to fraction form
   145,231.50/316,300.50 = 316,300.50/x
3. Step 3: Cross multiply
   145,231.50x = 316,300.50 × 316,300.50
4. Step 4: Simplify right side
   145,231.50x = 100,046,006,300.25
5. Step 5: Solve for x
   x = 100,046,006,300.25/145,231.50
6. Step 6: Final answer
   x = 688,872.64