Finding the Third Proportional to 172,300.50 and 378,580.50

Step by Step Solution

1. Step 1: Write the proportion equation
   172,300.50 : 378,580.50 = 378,580.50 : x
2. Step 2: Convert to fraction form
   172,300.50/378,580.50 = 378,580.50/x
3. Step 3: Cross multiply
   172,300.50x = 378,580.50 × 378,580.50
4. Step 4: Simplify right side
   172,300.50x = 143,323,194,980.25
5. Step 5: Solve for x
   x = 143,323,194,980.25/172,300.50
6. Step 6: Final answer
   x = 831,821.12