Finding the Fourth Proportional to 1,550.48, 2,139.66 and 921.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,550.48 : 2,139.66 = 921.32 : x
2. Step 2: Convert to fraction form
   1,550.48/2,139.66 = 921.32/x
3. Step 3: Cross multiply
   1,550.48x = 2,139.66 × 921.32
4. Step 4: Simplify right side
   1,550.48x = 1,971,300.85
5. Step 5: Solve for x
   x = 1,971,300.85/1,550.48
6. Step 6: Final answer
   x = 1,271.42