Finding the Third Proportional to 20,128.50 and 42,858

Step by Step Solution

1. Step 1: Write the proportion equation
   20,128.50 : 42,858 = 42,858 : x
2. Step 2: Convert to fraction form
   20,128.50/42,858 = 42,858/x
3. Step 3: Cross multiply
   20,128.50x = 42,858 × 42,858
4. Step 4: Simplify right side
   20,128.50x = 1,836,808,164
5. Step 5: Solve for x
   x = 1,836,808,164/20,128.50
6. Step 6: Final answer
   x = 91,254.10