Finding the Fourth Proportional to 21,806.81, 30,085.53 and 12,369.91

Step by Step Solution

1. Step 1: Write the proportion equation
   21,806.81 : 30,085.53 = 12,369.91 : x
2. Step 2: Convert to fraction form
   21,806.81/30,085.53 = 12,369.91/x
3. Step 3: Cross multiply
   21,806.81x = 30,085.53 × 12,369.91
4. Step 4: Simplify right side
   21,806.81x = 372,155,298.40
5. Step 5: Solve for x
   x = 372,155,298.40/21,806.81
6. Step 6: Final answer
   x = 17,066.01