Finding the Fourth Proportional to 1,381.92, 1,907.24 and 885.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.92 : 1,907.24 = 885.12 : x
2. Step 2: Convert to fraction form
   1,381.92/1,907.24 = 885.12/x
3. Step 3: Cross multiply
   1,381.92x = 1,907.24 × 885.12
4. Step 4: Simplify right side
   1,381.92x = 1,688,136.27
5. Step 5: Solve for x
   x = 1,688,136.27/1,381.92
6. Step 6: Final answer
   x = 1,221.59