Finding the Fourth Proportional to 1,215.18, 1,677.04 and 683.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,215.18 : 1,677.04 = 683.99 : x
2. Step 2: Convert to fraction form
   1,215.18/1,677.04 = 683.99/x
3. Step 3: Cross multiply
   1,215.18x = 1,677.04 × 683.99
4. Step 4: Simplify right side
   1,215.18x = 1,147,074.78
5. Step 5: Solve for x
   x = 1,147,074.78/1,215.18
6. Step 6: Final answer
   x = 943.95