Finding the Fourth Proportional to 1,564.78, 2,157.42 and 1,004.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,564.78 : 2,157.42 = 1,004.32 : x
2. Step 2: Convert to fraction form
   1,564.78/2,157.42 = 1,004.32/x
3. Step 3: Cross multiply
   1,564.78x = 2,157.42 × 1,004.32
4. Step 4: Simplify right side
   1,564.78x = 2,166,740.05
5. Step 5: Solve for x
   x = 2,166,740.05/1,564.78
6. Step 6: Final answer
   x = 1,384.69