Finding the Fourth Proportional to 21,748.91, 30,015.59 and 12,188.75

Step by Step Solution

1. Step 1: Write the proportion equation
   21,748.91 : 30,015.59 = 12,188.75 : x
2. Step 2: Convert to fraction form
   21,748.91/30,015.59 = 12,188.75/x
3. Step 3: Cross multiply
   21,748.91x = 30,015.59 × 12,188.75
4. Step 4: Simplify right side
   21,748.91x = 365,852,536.71
5. Step 5: Solve for x
   x = 365,852,536.71/21,748.91
6. Step 6: Final answer
   x = 16,821.65