Finding the Fourth Proportional to 42,889.79, 64,347.71 and 20,699.03

Step by Step Solution

1. Step 1: Write the proportion equation
   42,889.79 : 64,347.71 = 20,699.03 : x
2. Step 2: Convert to fraction form
   42,889.79/64,347.71 = 20,699.03/x
3. Step 3: Cross multiply
   42,889.79x = 64,347.71 × 20,699.03
4. Step 4: Simplify right side
   42,889.79x = 1,331,934,754.49
5. Step 5: Solve for x
   x = 1,331,934,754.49/42,889.79
6. Step 6: Final answer
   x = 31,054.82