Finding the Fourth Proportional to 1,019.64, 1,405.56 and 625.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.64 : 1,405.56 = 625.98 : x
2. Step 2: Convert to fraction form
   1,019.64/1,405.56 = 625.98/x
3. Step 3: Cross multiply
   1,019.64x = 1,405.56 × 625.98
4. Step 4: Simplify right side
   1,019.64x = 879,852.45
5. Step 5: Solve for x
   x = 879,852.45/1,019.64
6. Step 6: Final answer
   x = 862.90