Finding the Third Proportional to 100,520 and 209,308

Step by Step Solution

1. Step 1: Write the proportion equation
   100,520 : 209,308 = 209,308 : x
2. Step 2: Convert to fraction form
   100,520/209,308 = 209,308/x
3. Step 3: Cross multiply
   100,520x = 209,308 × 209,308
4. Step 4: Simplify right side
   100,520x = 43,809,838,864
5. Step 5: Solve for x
   x = 43,809,838,864/100,520
6. Step 6: Final answer
   x = 435,832.06