Finding the Fourth Proportional to 1,014.84, 1,401.39 and 642.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,014.84 : 1,401.39 = 642.48 : x
2. Step 2: Convert to fraction form
   1,014.84/1,401.39 = 642.48/x
3. Step 3: Cross multiply
   1,014.84x = 1,401.39 × 642.48
4. Step 4: Simplify right side
   1,014.84x = 900,365.05
5. Step 5: Solve for x
   x = 900,365.05/1,014.84
6. Step 6: Final answer
   x = 887.20