Finding the Fourth Proportional to 1,111.20, 1,532.88 and 691.44

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.20 : 1,532.88 = 691.44 : x
2. Step 2: Convert to fraction form
   1,111.20/1,532.88 = 691.44/x
3. Step 3: Cross multiply
   1,111.20x = 1,532.88 × 691.44
4. Step 4: Simplify right side
   1,111.20x = 1,059,894.55
5. Step 5: Solve for x
   x = 1,059,894.55/1,111.20
6. Step 6: Final answer
   x = 953.83