Finding the Fourth Proportional to 1,887.89, 2,606.50 and 1,215.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,887.89 : 2,606.50 = 1,215.99 : x
2. Step 2: Convert to fraction form
   1,887.89/2,606.50 = 1,215.99/x
3. Step 3: Cross multiply
   1,887.89x = 2,606.50 × 1,215.99
4. Step 4: Simplify right side
   1,887.89x = 3,169,477.94
5. Step 5: Solve for x
   x = 3,169,477.94/1,887.89
6. Step 6: Final answer
   x = 1,678.85