Finding the Fourth Proportional to 78,090.72, 107,764.20 and 42,279.92

Step by Step Solution

1. Step 1: Write the proportion equation
   78,090.72 : 107,764.20 = 42,279.92 : x
2. Step 2: Convert to fraction form
   78,090.72/107,764.20 = 42,279.92/x
3. Step 3: Cross multiply
   78,090.72x = 107,764.20 × 42,279.92
4. Step 4: Simplify right side
   78,090.72x = 4,556,261,754.86
5. Step 5: Solve for x
   x = 4,556,261,754.86/78,090.72
6. Step 6: Final answer
   x = 58,345.75