Finding the Fourth Proportional to 12,990.22, 19,499.12 and 10,554.45

Step by Step Solution

1. Step 1: Write the proportion equation
   12,990.22 : 19,499.12 = 10,554.45 : x
2. Step 2: Convert to fraction form
   12,990.22/19,499.12 = 10,554.45/x
3. Step 3: Cross multiply
   12,990.22x = 19,499.12 × 10,554.45
4. Step 4: Simplify right side
   12,990.22x = 205,802,487.08
5. Step 5: Solve for x
   x = 205,802,487.08/12,990.22
6. Step 6: Final answer
   x = 15,842.88