Finding the Fourth Proportional to 1,736.13, 2,603.72 and 810.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,736.13 : 2,603.72 = 810.78 : x
2. Step 2: Convert to fraction form
   1,736.13/2,603.72 = 810.78/x
3. Step 3: Cross multiply
   1,736.13x = 2,603.72 × 810.78
4. Step 4: Simplify right side
   1,736.13x = 2,111,044.10
5. Step 5: Solve for x
   x = 2,111,044.10/1,736.13
6. Step 6: Final answer
   x = 1,215.95