Finding the Fourth Proportional to 1,521.89, 2,100.31 and 858.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,521.89 : 2,100.31 = 858.50 : x
2. Step 2: Convert to fraction form
   1,521.89/2,100.31 = 858.50/x
3. Step 3: Cross multiply
   1,521.89x = 2,100.31 × 858.50
4. Step 4: Simplify right side
   1,521.89x = 1,803,111.84
5. Step 5: Solve for x
   x = 1,803,111.84/1,521.89
6. Step 6: Final answer
   x = 1,184.78