Finding the Fourth Proportional to 13,899.78, 19,181.70 and 7,931.34

Step by Step Solution

1. Step 1: Write the proportion equation
   13,899.78 : 19,181.70 = 7,931.34 : x
2. Step 2: Convert to fraction form
   13,899.78/19,181.70 = 7,931.34/x
3. Step 3: Cross multiply
   13,899.78x = 19,181.70 × 7,931.34
4. Step 4: Simplify right side
   13,899.78x = 152,136,584.48
5. Step 5: Solve for x
   x = 152,136,584.48/13,899.78
6. Step 6: Final answer
   x = 10,945.25