Finding the Fourth Proportional to 71,422.15, 107,155.86 and 42,990.24

Step by Step Solution

1. Step 1: Write the proportion equation
   71,422.15 : 107,155.86 = 42,990.24 : x
2. Step 2: Convert to fraction form
   71,422.15/107,155.86 = 42,990.24/x
3. Step 3: Cross multiply
   71,422.15x = 107,155.86 × 42,990.24
4. Step 4: Simplify right side
   71,422.15x = 4,606,656,138.81
5. Step 5: Solve for x
   x = 4,606,656,138.81/71,422.15
6. Step 6: Final answer
   x = 64,498.99