Finding the Fourth Proportional to 661,667.05, 991,918.18 and 262,588.15

Step by Step Solution

1. Step 1: Write the proportion equation
   661,667.05 : 991,918.18 = 262,588.15 : x
2. Step 2: Convert to fraction form
   661,667.05/991,918.18 = 262,588.15/x
3. Step 3: Cross multiply
   661,667.05x = 991,918.18 × 262,588.15
4. Step 4: Simplify right side
   661,667.05x = 260,465,959,837.57
5. Step 5: Solve for x
   x = 260,465,959,837.57/661,667.05
6. Step 6: Final answer
   x = 393,651.10