Finding the Third Proportional to 218,688 and 478,224

Step by Step Solution

1. Step 1: Write the proportion equation
   218,688 : 478,224 = 478,224 : x
2. Step 2: Convert to fraction form
   218,688/478,224 = 478,224/x
3. Step 3: Cross multiply
   218,688x = 478,224 × 478,224
4. Step 4: Simplify right side
   218,688x = 228,698,194,176
5. Step 5: Solve for x
   x = 228,698,194,176/218,688
6. Step 6: Final answer
   x = 1,045,773.86