Finding the Third Proportional to 287,136 and 427,898.25

Step by Step Solution

1. Step 1: Write the proportion equation
   287,136 : 427,898.25 = 427,898.25 : x
2. Step 2: Convert to fraction form
   287,136/427,898.25 = 427,898.25/x
3. Step 3: Cross multiply
   287,136x = 427,898.25 × 427,898.25
4. Step 4: Simplify right side
   287,136x = 183,096,912,353.06
5. Step 5: Solve for x
   x = 183,096,912,353.06/287,136
6. Step 6: Final answer
   x = 637,666.17