Finding the Fourth Proportional to 42,769.61, 64,150.28 and 13,179.50

Step by Step Solution

1. Step 1: Write the proportion equation
   42,769.61 : 64,150.28 = 13,179.50 : x
2. Step 2: Convert to fraction form
   42,769.61/64,150.28 = 13,179.50/x
3. Step 3: Cross multiply
   42,769.61x = 64,150.28 × 13,179.50
4. Step 4: Simplify right side
   42,769.61x = 845,468,294.51
5. Step 5: Solve for x
   x = 845,468,294.51/42,769.61
6. Step 6: Final answer
   x = 19,767.97