Finding the Fourth Proportional to 1,439.32, 1,986.58 and 915.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,439.32 : 1,986.58 = 915.25 : x
2. Step 2: Convert to fraction form
   1,439.32/1,986.58 = 915.25/x
3. Step 3: Cross multiply
   1,439.32x = 1,986.58 × 915.25
4. Step 4: Simplify right side
   1,439.32x = 1,818,217.35
5. Step 5: Solve for x
   x = 1,818,217.35/1,439.32
6. Step 6: Final answer
   x = 1,263.25