Finding the Fourth Proportional to 1,099.72, 1,518.82 and 853.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,099.72 : 1,518.82 = 853.98 : x
2. Step 2: Convert to fraction form
   1,099.72/1,518.82 = 853.98/x
3. Step 3: Cross multiply
   1,099.72x = 1,518.82 × 853.98
4. Step 4: Simplify right side
   1,099.72x = 1,297,041.90
5. Step 5: Solve for x
   x = 1,297,041.90/1,099.72
6. Step 6: Final answer
   x = 1,179.43