Finding the Fourth Proportional to 1,392.21, 1,921.01 and 802.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,392.21 : 1,921.01 = 802.62 : x
2. Step 2: Convert to fraction form
   1,392.21/1,921.01 = 802.62/x
3. Step 3: Cross multiply
   1,392.21x = 1,921.01 × 802.62
4. Step 4: Simplify right side
   1,392.21x = 1,541,837.03
5. Step 5: Solve for x
   x = 1,541,837.03/1,392.21
6. Step 6: Final answer
   x = 1,107.47