Finding the Third Proportional to 21,390.75 and 28,643.63

Step by Step Solution

1. Step 1: Write the proportion equation
   21,390.75 : 28,643.63 = 28,643.63 : x
2. Step 2: Convert to fraction form
   21,390.75/28,643.63 = 28,643.63/x
3. Step 3: Cross multiply
   21,390.75x = 28,643.63 × 28,643.63
4. Step 4: Simplify right side
   21,390.75x = 820,457,253.14
5. Step 5: Solve for x
   x = 820,457,253.14/21,390.75
6. Step 6: Final answer
   x = 38,355.70