Finding the Fourth Proportional to 1,544.78, 2,131.83 and 947.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,544.78 : 2,131.83 = 947.21 : x
2. Step 2: Convert to fraction form
   1,544.78/2,131.83 = 947.21/x
3. Step 3: Cross multiply
   1,544.78x = 2,131.83 × 947.21
4. Step 4: Simplify right side
   1,544.78x = 2,019,280.04
5. Step 5: Solve for x
   x = 2,019,280.04/1,544.78
6. Step 6: Final answer
   x = 1,307.17