Finding the Fourth Proportional to 1,062.07, 1,465.30 and 642.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,062.07 : 1,465.30 = 642.55 : x
2. Step 2: Convert to fraction form
   1,062.07/1,465.30 = 642.55/x
3. Step 3: Cross multiply
   1,062.07x = 1,465.30 × 642.55
4. Step 4: Simplify right side
   1,062.07x = 941,528.52
5. Step 5: Solve for x
   x = 941,528.52/1,062.07
6. Step 6: Final answer
   x = 886.50