Finding the Fourth Proportional to 1,554.92, 2,145.86 and 891.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,554.92 : 2,145.86 = 891.72 : x
2. Step 2: Convert to fraction form
   1,554.92/2,145.86 = 891.72/x
3. Step 3: Cross multiply
   1,554.92x = 2,145.86 × 891.72
4. Step 4: Simplify right side
   1,554.92x = 1,913,506.28
5. Step 5: Solve for x
   x = 1,913,506.28/1,554.92
6. Step 6: Final answer
   x = 1,230.61