Finding the Fourth Proportional to 21,066.10, 31,602.38 and 7,919.39

Step by Step Solution

1. Step 1: Write the proportion equation
   21,066.10 : 31,602.38 = 7,919.39 : x
2. Step 2: Convert to fraction form
   21,066.10/31,602.38 = 7,919.39/x
3. Step 3: Cross multiply
   21,066.10x = 31,602.38 × 7,919.39
4. Step 4: Simplify right side
   21,066.10x = 250,271,572.15
5. Step 5: Solve for x
   x = 250,271,572.15/21,066.10
6. Step 6: Final answer
   x = 11,880.30