Finding the Third Proportional to 21.00 and 42.83

Step by Step Solution

1. Step 1: Write the proportion equation
   21.00 : 42.83 = 42.83 : x
2. Step 2: Convert to fraction form
   21.00/42.83 = 42.83/x
3. Step 3: Cross multiply
   21.00x = 42.83 × 42.83
4. Step 4: Simplify right side
   21.00x = 1,834.71
5. Step 5: Solve for x
   x = 1,834.71/21.00
6. Step 6: Final answer
   x = 87.36