Finding the Fourth Proportional to 1,101.48, 1,519.62 and 687.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,101.48 : 1,519.62 = 687.72 : x
2. Step 2: Convert to fraction form
   1,101.48/1,519.62 = 687.72/x
3. Step 3: Cross multiply
   1,101.48x = 1,519.62 × 687.72
4. Step 4: Simplify right side
   1,101.48x = 1,045,073.07
5. Step 5: Solve for x
   x = 1,045,073.07/1,101.48
6. Step 6: Final answer
   x = 948.79