Finding the Third Proportional to 319,632 and 689,079.75

Step by Step Solution

1. Step 1: Write the proportion equation
   319,632 : 689,079.75 = 689,079.75 : x
2. Step 2: Convert to fraction form
   319,632/689,079.75 = 689,079.75/x
3. Step 3: Cross multiply
   319,632x = 689,079.75 × 689,079.75
4. Step 4: Simplify right side
   319,632x = 474,830,901,860.06
5. Step 5: Solve for x
   x = 474,830,901,860.06/319,632
6. Step 6: Final answer
   x = 1,485,554.96