Finding the Fourth Proportional to 9,378.90, 12,942.72 and 5,400

Step by Step Solution

1. Step 1: Write the proportion equation
   9,378.90 : 12,942.72 = 5,400 : x
2. Step 2: Convert to fraction form
   9,378.90/12,942.72 = 5,400/x
3. Step 3: Cross multiply
   9,378.90x = 12,942.72 × 5,400
4. Step 4: Simplify right side
   9,378.90x = 69,890,688
5. Step 5: Solve for x
   x = 69,890,688/9,378.90
6. Step 6: Final answer
   x = 7,451.91