Finding the Fourth Proportional to 1,071.61, 1,479.01 and 623.54

Step by Step Solution

1. Step 1: Write the proportion equation
   1,071.61 : 1,479.01 = 623.54 : x
2. Step 2: Convert to fraction form
   1,071.61/1,479.01 = 623.54/x
3. Step 3: Cross multiply
   1,071.61x = 1,479.01 × 623.54
4. Step 4: Simplify right side
   1,071.61x = 922,221.90
5. Step 5: Solve for x
   x = 922,221.90/1,071.61
6. Step 6: Final answer
   x = 860.59