Finding the Fourth Proportional to 1,071.84, 1,481.04 and 840.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,071.84 : 1,481.04 = 840.72 : x
2. Step 2: Convert to fraction form
   1,071.84/1,481.04 = 840.72/x
3. Step 3: Cross multiply
   1,071.84x = 1,481.04 × 840.72
4. Step 4: Simplify right side
   1,071.84x = 1,245,139.95
5. Step 5: Solve for x
   x = 1,245,139.95/1,071.84
6. Step 6: Final answer
   x = 1,161.68