Finding the Fourth Proportional to 65,657.76, 91,219.40 and 64,870.44

Step by Step Solution

1. Step 1: Write the proportion equation
   65,657.76 : 91,219.40 = 64,870.44 : x
2. Step 2: Convert to fraction form
   65,657.76/91,219.40 = 64,870.44/x
3. Step 3: Cross multiply
   65,657.76x = 91,219.40 × 64,870.44
4. Step 4: Simplify right side
   65,657.76x = 5,917,442,614.54
5. Step 5: Solve for x
   x = 5,917,442,614.54/65,657.76
6. Step 6: Final answer
   x = 90,125.56