Finding the Fourth Proportional to 1,051.89, 1,578.15 and 321.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,051.89 : 1,578.15 = 321.45 : x
2. Step 2: Convert to fraction form
   1,051.89/1,578.15 = 321.45/x
3. Step 3: Cross multiply
   1,051.89x = 1,578.15 × 321.45
4. Step 4: Simplify right side
   1,051.89x = 507,296.32
5. Step 5: Solve for x
   x = 507,296.32/1,051.89
6. Step 6: Final answer
   x = 482.27