Finding the Fourth Proportional to 2,214.40, 3,320.16 and 915.52

Step by Step Solution

1. Step 1: Write the proportion equation
   2,214.40 : 3,320.16 = 915.52 : x
2. Step 2: Convert to fraction form
   2,214.40/3,320.16 = 915.52/x
3. Step 3: Cross multiply
   2,214.40x = 3,320.16 × 915.52
4. Step 4: Simplify right side
   2,214.40x = 3,039,672.88
5. Step 5: Solve for x
   x = 3,039,672.88/2,214.40
6. Step 6: Final answer
   x = 1,372.68