Finding the Fourth Proportional to 1,445.75, 1,995.72 and 915.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,445.75 : 1,995.72 = 915.40 : x
2. Step 2: Convert to fraction form
   1,445.75/1,995.72 = 915.40/x
3. Step 3: Cross multiply
   1,445.75x = 1,995.72 × 915.40
4. Step 4: Simplify right side
   1,445.75x = 1,826,872.11
5. Step 5: Solve for x
   x = 1,826,872.11/1,445.75
6. Step 6: Final answer
   x = 1,263.62