Finding the Third Proportional to 18,990 and 30,811.50

Step by Step Solution

1. Step 1: Write the proportion equation
   18,990 : 30,811.50 = 30,811.50 : x
2. Step 2: Convert to fraction form
   18,990/30,811.50 = 30,811.50/x
3. Step 3: Cross multiply
   18,990x = 30,811.50 × 30,811.50
4. Step 4: Simplify right side
   18,990x = 949,348,532.25
5. Step 5: Solve for x
   x = 949,348,532.25/18,990
6. Step 6: Final answer
   x = 49,992.02