Finding the Fourth Proportional to 65,961.06, 91,021.92 and 42,085.20

Step by Step Solution

1. Step 1: Write the proportion equation
   65,961.06 : 91,021.92 = 42,085.20 : x
2. Step 2: Convert to fraction form
   65,961.06/91,021.92 = 42,085.20/x
3. Step 3: Cross multiply
   65,961.06x = 91,021.92 × 42,085.20
4. Step 4: Simplify right side
   65,961.06x = 3,830,675,707.58
5. Step 5: Solve for x
   x = 3,830,675,707.58/65,961.06
6. Step 6: Final answer
   x = 58,074.81