Finding the Fourth Proportional to 1,081.72, 1,621.46 and 561.08

Step by Step Solution

1. Step 1: Write the proportion equation
   1,081.72 : 1,621.46 = 561.08 : x
2. Step 2: Convert to fraction form
   1,081.72/1,621.46 = 561.08/x
3. Step 3: Cross multiply
   1,081.72x = 1,621.46 × 561.08
4. Step 4: Simplify right side
   1,081.72x = 909,768.78
5. Step 5: Solve for x
   x = 909,768.78/1,081.72
6. Step 6: Final answer
   x = 841.04