Finding the Fourth Proportional to 1,402.58, 2,101.55 and 853.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,402.58 : 2,101.55 = 853.10 : x
2. Step 2: Convert to fraction form
   1,402.58/2,101.55 = 853.10/x
3. Step 3: Cross multiply
   1,402.58x = 2,101.55 × 853.10
4. Step 4: Simplify right side
   1,402.58x = 1,792,817.53
5. Step 5: Solve for x
   x = 1,792,817.53/1,402.58
6. Step 6: Final answer
   x = 1,278.23