Finding the Fourth Proportional to 21,111.64, 31,676.18 and 9,259.28

Step by Step Solution

1. Step 1: Write the proportion equation
   21,111.64 : 31,676.18 = 9,259.28 : x
2. Step 2: Convert to fraction form
   21,111.64/31,676.18 = 9,259.28/x
3. Step 3: Cross multiply
   21,111.64x = 31,676.18 × 9,259.28
4. Step 4: Simplify right side
   21,111.64x = 293,298,619.95
5. Step 5: Solve for x
   x = 293,298,619.95/21,111.64
6. Step 6: Final answer
   x = 13,892.74