Finding the Fourth Proportional to 1,290.72, 1,935.72 and 560.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,290.72 : 1,935.72 = 560.10 : x
2. Step 2: Convert to fraction form
   1,290.72/1,935.72 = 560.10/x
3. Step 3: Cross multiply
   1,290.72x = 1,935.72 × 560.10
4. Step 4: Simplify right side
   1,290.72x = 1,084,196.77
5. Step 5: Solve for x
   x = 1,084,196.77/1,290.72
6. Step 6: Final answer
   x = 839.99