Finding the Third Proportional to 336,990 and 721,364.50

Step by Step Solution

1. Step 1: Write the proportion equation
   336,990 : 721,364.50 = 721,364.50 : x
2. Step 2: Convert to fraction form
   336,990/721,364.50 = 721,364.50/x
3. Step 3: Cross multiply
   336,990x = 721,364.50 × 721,364.50
4. Step 4: Simplify right side
   336,990x = 520,366,741,860.25
5. Step 5: Solve for x
   x = 520,366,741,860.25/336,990
6. Step 6: Final answer
   x = 1,544,160.78