Finding the Fourth Proportional to 5,259.35, 7,890.68 and 1,561.60

Step by Step Solution

1. Step 1: Write the proportion equation
   5,259.35 : 7,890.68 = 1,561.60 : x
2. Step 2: Convert to fraction form
   5,259.35/7,890.68 = 1,561.60/x
3. Step 3: Cross multiply
   5,259.35x = 7,890.68 × 1,561.60
4. Step 4: Simplify right side
   5,259.35x = 12,322,085.89
5. Step 5: Solve for x
   x = 12,322,085.89/5,259.35
6. Step 6: Final answer
   x = 2,342.89