Finding the Fourth Proportional to 1,279.98, 1,764.54 and 1,056.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,279.98 : 1,764.54 = 1,056.09 : x
2. Step 2: Convert to fraction form
   1,279.98/1,764.54 = 1,056.09/x
3. Step 3: Cross multiply
   1,279.98x = 1,764.54 × 1,056.09
4. Step 4: Simplify right side
   1,279.98x = 1,863,513.05
5. Step 5: Solve for x
   x = 1,863,513.05/1,279.98
6. Step 6: Final answer
   x = 1,455.89