Finding the Fourth Proportional to 64,779.89, 89,345.43 and 42,126.21

Step by Step Solution

1. Step 1: Write the proportion equation
   64,779.89 : 89,345.43 = 42,126.21 : x
2. Step 2: Convert to fraction form
   64,779.89/89,345.43 = 42,126.21/x
3. Step 3: Cross multiply
   64,779.89x = 89,345.43 × 42,126.21
4. Step 4: Simplify right side
   64,779.89x = 3,763,784,346.72
5. Step 5: Solve for x
   x = 3,763,784,346.72/64,779.89
6. Step 6: Final answer
   x = 58,101.13