Finding the Third Proportional to 686,271 and 990,037.50

Step by Step Solution

1. Step 1: Write the proportion equation
   686,271 : 990,037.50 = 990,037.50 : x
2. Step 2: Convert to fraction form
   686,271/990,037.50 = 990,037.50/x
3. Step 3: Cross multiply
   686,271x = 990,037.50 × 990,037.50
4. Step 4: Simplify right side
   686,271x = 980,174,251,406.25
5. Step 5: Solve for x
   x = 980,174,251,406.25/686,271
6. Step 6: Final answer
   x = 1,428,261.21