Finding the Fourth Proportional to 3,947.31, 5,919.72 and 3,688.50

Step by Step Solution

1. Step 1: Write the proportion equation
   3,947.31 : 5,919.72 = 3,688.50 : x
2. Step 2: Convert to fraction form
   3,947.31/5,919.72 = 3,688.50/x
3. Step 3: Cross multiply
   3,947.31x = 5,919.72 × 3,688.50
4. Step 4: Simplify right side
   3,947.31x = 21,834,887.22
5. Step 5: Solve for x
   x = 21,834,887.22/3,947.31
6. Step 6: Final answer
   x = 5,531.59