Finding the Fourth Proportional to 1,385.50, 1,912.59 and 920.02

Step by Step Solution

1. Step 1: Write the proportion equation
   1,385.50 : 1,912.59 = 920.02 : x
2. Step 2: Convert to fraction form
   1,385.50/1,912.59 = 920.02/x
3. Step 3: Cross multiply
   1,385.50x = 1,912.59 × 920.02
4. Step 4: Simplify right side
   1,385.50x = 1,759,621.05
5. Step 5: Solve for x
   x = 1,759,621.05/1,385.50
6. Step 6: Final answer
   x = 1,270.03