Finding the Third Proportional to 139,440 and 210,472

Step by Step Solution

1. Step 1: Write the proportion equation
   139,440 : 210,472 = 210,472 : x
2. Step 2: Convert to fraction form
   139,440/210,472 = 210,472/x
3. Step 3: Cross multiply
   139,440x = 210,472 × 210,472
4. Step 4: Simplify right side
   139,440x = 44,298,462,784
5. Step 5: Solve for x
   x = 44,298,462,784/139,440
6. Step 6: Final answer
   x = 317,688.34