Finding the Fourth Proportional to 1,538.16, 2,122.72 and 866.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,538.16 : 2,122.72 = 866.10 : x
2. Step 2: Convert to fraction form
   1,538.16/2,122.72 = 866.10/x
3. Step 3: Cross multiply
   1,538.16x = 2,122.72 × 866.10
4. Step 4: Simplify right side
   1,538.16x = 1,838,487.79
5. Step 5: Solve for x
   x = 1,838,487.79/1,538.16
6. Step 6: Final answer
   x = 1,195.25