Finding the Fourth Proportional to 9,356.30, 12,911.51 and 5,377.31

Step by Step Solution

1. Step 1: Write the proportion equation
   9,356.30 : 12,911.51 = 5,377.31 : x
2. Step 2: Convert to fraction form
   9,356.30/12,911.51 = 5,377.31/x
3. Step 3: Cross multiply
   9,356.30x = 12,911.51 × 5,377.31
4. Step 4: Simplify right side
   9,356.30x = 69,429,164.95
5. Step 5: Solve for x
   x = 69,429,164.95/9,356.30
6. Step 6: Final answer
   x = 7,420.58