Finding the Fourth Proportional to 1,078.72, 1,615.17 and 748.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.72 : 1,615.17 = 748.98 : x
2. Step 2: Convert to fraction form
   1,078.72/1,615.17 = 748.98/x
3. Step 3: Cross multiply
   1,078.72x = 1,615.17 × 748.98
4. Step 4: Simplify right side
   1,078.72x = 1,209,732.84
5. Step 5: Solve for x
   x = 1,209,732.84/1,078.72
6. Step 6: Final answer
   x = 1,121.45