Finding the Fourth Proportional to 1,623.88, 2,240.71 and 915.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,623.88 : 2,240.71 = 915.69 : x
2. Step 2: Convert to fraction form
   1,623.88/2,240.71 = 915.69/x
3. Step 3: Cross multiply
   1,623.88x = 2,240.71 × 915.69
4. Step 4: Simplify right side
   1,623.88x = 2,051,801.85
5. Step 5: Solve for x
   x = 2,051,801.85/1,623.88
6. Step 6: Final answer
   x = 1,263.52