Finding the Fourth Proportional to 290,636.76, 435,980.16 and 80,274.72

Step by Step Solution

1. Step 1: Write the proportion equation
   290,636.76 : 435,980.16 = 80,274.72 : x
2. Step 2: Convert to fraction form
   290,636.76/435,980.16 = 80,274.72/x
3. Step 3: Cross multiply
   290,636.76x = 435,980.16 × 80,274.72
4. Step 4: Simplify right side
   290,636.76x = 34,998,185,269.56
5. Step 5: Solve for x
   x = 34,998,185,269.56/290,636.76
6. Step 6: Final answer
   x = 120,418.99