Finding the Fourth Proportional to 1,521.81, 2,100.20 and 858.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,521.81 : 2,100.20 = 858.42 : x
2. Step 2: Convert to fraction form
   1,521.81/2,100.20 = 858.42/x
3. Step 3: Cross multiply
   1,521.81x = 2,100.20 × 858.42
4. Step 4: Simplify right side
   1,521.81x = 1,802,849.39
5. Step 5: Solve for x
   x = 1,802,849.39/1,521.81
6. Step 6: Final answer
   x = 1,184.67