Finding the Fourth Proportional to 1,061.93, 1,465.76 and 642.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.93 : 1,465.76 = 642.28 : x
2. Step 2: Convert to fraction form
   1,061.93/1,465.76 = 642.28/x
3. Step 3: Cross multiply
   1,061.93x = 1,465.76 × 642.28
4. Step 4: Simplify right side
   1,061.93x = 941,426.27
5. Step 5: Solve for x
   x = 941,426.27/1,061.93
6. Step 6: Final answer
   x = 886.53