Finding the Fourth Proportional to 9,621.96, 13,276.62 and 5,429.40

Step by Step Solution

1. Step 1: Write the proportion equation
   9,621.96 : 13,276.62 = 5,429.40 : x
2. Step 2: Convert to fraction form
   9,621.96/13,276.62 = 5,429.40/x
3. Step 3: Cross multiply
   9,621.96x = 13,276.62 × 5,429.40
4. Step 4: Simplify right side
   9,621.96x = 72,084,080.63
5. Step 5: Solve for x
   x = 72,084,080.63/9,621.96
6. Step 6: Final answer
   x = 7,491.62