Finding the Fourth Proportional to 13,781.98, 19,019.56 and 7,813.90

Step by Step Solution

1. Step 1: Write the proportion equation
   13,781.98 : 19,019.56 = 7,813.90 : x
2. Step 2: Convert to fraction form
   13,781.98/19,019.56 = 7,813.90/x
3. Step 3: Cross multiply
   13,781.98x = 19,019.56 × 7,813.90
4. Step 4: Simplify right side
   13,781.98x = 148,616,958.77
5. Step 5: Solve for x
   x = 148,616,958.77/13,781.98
6. Step 6: Final answer
   x = 10,783.42