Finding the Fourth Proportional to 9,907.63, 13,672.50 and 5,431.57

Step by Step Solution

1. Step 1: Write the proportion equation
   9,907.63 : 13,672.50 = 5,431.57 : x
2. Step 2: Convert to fraction form
   9,907.63/13,672.50 = 5,431.57/x
3. Step 3: Cross multiply
   9,907.63x = 13,672.50 × 5,431.57
4. Step 4: Simplify right side
   9,907.63x = 74,263,140.83
5. Step 5: Solve for x
   x = 74,263,140.83/9,907.63
6. Step 6: Final answer
   x = 7,495.55