Finding the Fourth Proportional to 77,890.79, 107,489.34 and 42,080.79

Step by Step Solution

1. Step 1: Write the proportion equation
   77,890.79 : 107,489.34 = 42,080.79 : x
2. Step 2: Convert to fraction form
   77,890.79/107,489.34 = 42,080.79/x
3. Step 3: Cross multiply
   77,890.79x = 107,489.34 × 42,080.79
4. Step 4: Simplify right side
   77,890.79x = 4,523,236,343.78
5. Step 5: Solve for x
   x = 4,523,236,343.78/77,890.79
6. Step 6: Final answer
   x = 58,071.52