Finding the Third Proportional to 90,990 and 191,406

Step by Step Solution

1. Step 1: Write the proportion equation
   90,990 : 191,406 = 191,406 : x
2. Step 2: Convert to fraction form
   90,990/191,406 = 191,406/x
3. Step 3: Cross multiply
   90,990x = 191,406 × 191,406
4. Step 4: Simplify right side
   90,990x = 36,636,256,836
5. Step 5: Solve for x
   x = 36,636,256,836/90,990
6. Step 6: Final answer
   x = 402,640.48