Finding the Fourth Proportional to 2,647.69, 3,973.35 and 916.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,647.69 : 3,973.35 = 916.31 : x
2. Step 2: Convert to fraction form
   2,647.69/3,973.35 = 916.31/x
3. Step 3: Cross multiply
   2,647.69x = 3,973.35 × 916.31
4. Step 4: Simplify right side
   2,647.69x = 3,640,833.71
5. Step 5: Solve for x
   x = 3,640,833.71/2,647.69
6. Step 6: Final answer
   x = 1,375.10