Finding the Fourth Proportional to 1,558.83, 2,151.60 and 921.33

Step by Step Solution

1. Step 1: Write the proportion equation
   1,558.83 : 2,151.60 = 921.33 : x
2. Step 2: Convert to fraction form
   1,558.83/2,151.60 = 921.33/x
3. Step 3: Cross multiply
   1,558.83x = 2,151.60 × 921.33
4. Step 4: Simplify right side
   1,558.83x = 1,982,333.63
5. Step 5: Solve for x
   x = 1,982,333.63/1,558.83
6. Step 6: Final answer
   x = 1,271.68