Finding the Fourth Proportional to 1,900.72, 2,623.24 and 1,311.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,900.72 : 2,623.24 = 1,311.60 : x
2. Step 2: Convert to fraction form
   1,900.72/2,623.24 = 1,311.60/x
3. Step 3: Cross multiply
   1,900.72x = 2,623.24 × 1,311.60
4. Step 4: Simplify right side
   1,900.72x = 3,440,641.58
5. Step 5: Solve for x
   x = 3,440,641.58/1,900.72
6. Step 6: Final answer
   x = 1,810.18