Finding the Fourth Proportional to 1,128.58, 1,692.72 and 479.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,128.58 : 1,692.72 = 479.38 : x
2. Step 2: Convert to fraction form
   1,128.58/1,692.72 = 479.38/x
3. Step 3: Cross multiply
   1,128.58x = 1,692.72 × 479.38
4. Step 4: Simplify right side
   1,128.58x = 811,456.11
5. Step 5: Solve for x
   x = 811,456.11/1,128.58
6. Step 6: Final answer
   x = 719.01