Finding the Fourth Proportional to 42,669.16, 64,016.04 and 13,091.35

Step by Step Solution

1. Step 1: Write the proportion equation
   42,669.16 : 64,016.04 = 13,091.35 : x
2. Step 2: Convert to fraction form
   42,669.16/64,016.04 = 13,091.35/x
3. Step 3: Cross multiply
   42,669.16x = 64,016.04 × 13,091.35
4. Step 4: Simplify right side
   42,669.16x = 838,056,385.25
5. Step 5: Solve for x
   x = 838,056,385.25/42,669.16
6. Step 6: Final answer
   x = 19,640.80