Finding the Fourth Proportional to 78,919.61, 118,357.25 and 21,980.57

Step by Step Solution

1. Step 1: Write the proportion equation
   78,919.61 : 118,357.25 = 21,980.57 : x
2. Step 2: Convert to fraction form
   78,919.61/118,357.25 = 21,980.57/x
3. Step 3: Cross multiply
   78,919.61x = 118,357.25 × 21,980.57
4. Step 4: Simplify right side
   78,919.61x = 2,601,559,116.94
5. Step 5: Solve for x
   x = 2,601,559,116.94/78,919.61
6. Step 6: Final answer
   x = 32,964.67