Finding the Fourth Proportional to 21,837.42, 30,135.78 and 12,406.14

Step by Step Solution

1. Step 1: Write the proportion equation
   21,837.42 : 30,135.78 = 12,406.14 : x
2. Step 2: Convert to fraction form
   21,837.42/30,135.78 = 12,406.14/x
3. Step 3: Cross multiply
   21,837.42x = 30,135.78 × 12,406.14
4. Step 4: Simplify right side
   21,837.42x = 373,868,705.69
5. Step 5: Solve for x
   x = 373,868,705.69/21,837.42
6. Step 6: Final answer
   x = 17,120.55