Finding the Third Proportional to 20,756.50 and 42,990.50

Step by Step Solution

1. Step 1: Write the proportion equation
   20,756.50 : 42,990.50 = 42,990.50 : x
2. Step 2: Convert to fraction form
   20,756.50/42,990.50 = 42,990.50/x
3. Step 3: Cross multiply
   20,756.50x = 42,990.50 × 42,990.50
4. Step 4: Simplify right side
   20,756.50x = 1,848,183,090.25
5. Step 5: Solve for x
   x = 1,848,183,090.25/20,756.50
6. Step 6: Final answer
   x = 89,041.17