Finding the Third Proportional to 12,990 and 28,458

Step by Step Solution

1. Step 1: Write the proportion equation
   12,990 : 28,458 = 28,458 : x
2. Step 2: Convert to fraction form
   12,990/28,458 = 28,458/x
3. Step 3: Cross multiply
   12,990x = 28,458 × 28,458
4. Step 4: Simplify right side
   12,990x = 809,857,764
5. Step 5: Solve for x
   x = 809,857,764/12,990
6. Step 6: Final answer
   x = 62,344.71