Finding the Third Proportional to 128,990 and 195,432.50

Step by Step Solution

1. Step 1: Write the proportion equation
   128,990 : 195,432.50 = 195,432.50 : x
2. Step 2: Convert to fraction form
   128,990/195,432.50 = 195,432.50/x
3. Step 3: Cross multiply
   128,990x = 195,432.50 × 195,432.50
4. Step 4: Simplify right side
   128,990x = 38,193,862,056.25
5. Step 5: Solve for x
   x = 38,193,862,056.25/128,990
6. Step 6: Final answer
   x = 296,099.40