Finding the Third Proportional to 428,643 and 916,339.50

Step by Step Solution

1. Step 1: Write the proportion equation
   428,643 : 916,339.50 = 916,339.50 : x
2. Step 2: Convert to fraction form
   428,643/916,339.50 = 916,339.50/x
3. Step 3: Cross multiply
   428,643x = 916,339.50 × 916,339.50
4. Step 4: Simplify right side
   428,643x = 839,678,079,260.25
5. Step 5: Solve for x
   x = 839,678,079,260.25/428,643
6. Step 6: Final answer
   x = 1,958,921.71