Finding the Fourth Proportional to 1,111.52, 1,531.20 and 779.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.52 : 1,531.20 = 779.30 : x
2. Step 2: Convert to fraction form
   1,111.52/1,531.20 = 779.30/x
3. Step 3: Cross multiply
   1,111.52x = 1,531.20 × 779.30
4. Step 4: Simplify right side
   1,111.52x = 1,193,264.16
5. Step 5: Solve for x
   x = 1,193,264.16/1,111.52
6. Step 6: Final answer
   x = 1,073.54