Finding the Fourth Proportional to 78,780.74, 108,715.59 and 42,971.05

Step by Step Solution

1. Step 1: Write the proportion equation
   78,780.74 : 108,715.59 = 42,971.05 : x
2. Step 2: Convert to fraction form
   78,780.74/108,715.59 = 42,971.05/x
3. Step 3: Cross multiply
   78,780.74x = 108,715.59 × 42,971.05
4. Step 4: Simplify right side
   78,780.74x = 4,671,622,781.88
5. Step 5: Solve for x
   x = 4,671,622,781.88/78,780.74
6. Step 6: Final answer
   x = 59,299.04