Finding the Fourth Proportional to 1,312.25, 1,809.45 and 1,112.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,312.25 : 1,809.45 = 1,112.31 : x
2. Step 2: Convert to fraction form
   1,312.25/1,809.45 = 1,112.31/x
3. Step 3: Cross multiply
   1,312.25x = 1,809.45 × 1,112.31
4. Step 4: Simplify right side
   1,312.25x = 2,012,669.33
5. Step 5: Solve for x
   x = 2,012,669.33/1,312.25
6. Step 6: Final answer
   x = 1,533.76