Finding the Fourth Proportional to 1,590.84, 2,196.78 and 1,128.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,590.84 : 2,196.78 = 1,128.12 : x
2. Step 2: Convert to fraction form
   1,590.84/2,196.78 = 1,128.12/x
3. Step 3: Cross multiply
   1,590.84x = 2,196.78 × 1,128.12
4. Step 4: Simplify right side
   1,590.84x = 2,478,231.45
5. Step 5: Solve for x
   x = 2,478,231.45/1,590.84
6. Step 6: Final answer
   x = 1,557.81