Finding the Fourth Proportional to 1,367.64, 1,887.56 and 870.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,367.64 : 1,887.56 = 870.50 : x
2. Step 2: Convert to fraction form
   1,367.64/1,887.56 = 870.50/x
3. Step 3: Cross multiply
   1,367.64x = 1,887.56 × 870.50
4. Step 4: Simplify right side
   1,367.64x = 1,643,107.19
5. Step 5: Solve for x
   x = 1,643,107.19/1,367.64
6. Step 6: Final answer
   x = 1,201.42