Finding the Third Proportional to 316,791 and 689,350.50

Step by Step Solution

1. Step 1: Write the proportion equation
   316,791 : 689,350.50 = 689,350.50 : x
2. Step 2: Convert to fraction form
   316,791/689,350.50 = 689,350.50/x
3. Step 3: Cross multiply
   316,791x = 689,350.50 × 689,350.50
4. Step 4: Simplify right side
   316,791x = 475,204,111,850.25
5. Step 5: Solve for x
   x = 475,204,111,850.25/316,791
6. Step 6: Final answer
   x = 1,500,055.59