Finding the Fourth Proportional to 1,996.32, 2,991.60 and 1,128.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,996.32 : 2,991.60 = 1,128.78 : x
2. Step 2: Convert to fraction form
   1,996.32/2,991.60 = 1,128.78/x
3. Step 3: Cross multiply
   1,996.32x = 2,991.60 × 1,128.78
4. Step 4: Simplify right side
   1,996.32x = 3,376,858.25
5. Step 5: Solve for x
   x = 3,376,858.25/1,996.32
6. Step 6: Final answer
   x = 1,691.54