Finding the Fourth Proportional to 1,219.51, 1,682.94 and 688.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,219.51 : 1,682.94 = 688.42 : x
2. Step 2: Convert to fraction form
   1,219.51/1,682.94 = 688.42/x
3. Step 3: Cross multiply
   1,219.51x = 1,682.94 × 688.42
4. Step 4: Simplify right side
   1,219.51x = 1,158,569.55
5. Step 5: Solve for x
   x = 1,158,569.55/1,219.51
6. Step 6: Final answer
   x = 950.03