Finding the Fourth Proportional to 71,690.70, 107,499.60 and 42,117.60

Step by Step Solution

1. Step 1: Write the proportion equation
   71,690.70 : 107,499.60 = 42,117.60 : x
2. Step 2: Convert to fraction form
   71,690.70/107,499.60 = 42,117.60/x
3. Step 3: Cross multiply
   71,690.70x = 107,499.60 × 42,117.60
4. Step 4: Simplify right side
   71,690.70x = 4,527,625,152.96
5. Step 5: Solve for x
   x = 4,527,625,152.96/71,690.70
6. Step 6: Final answer
   x = 63,154.99