Finding the Fourth Proportional to 42,993.84, 64,505.88 and 13,419.12

Step by Step Solution

1. Step 1: Write the proportion equation
   42,993.84 : 64,505.88 = 13,419.12 : x
2. Step 2: Convert to fraction form
   42,993.84/64,505.88 = 13,419.12/x
3. Step 3: Cross multiply
   42,993.84x = 64,505.88 × 13,419.12
4. Step 4: Simplify right side
   42,993.84x = 865,612,144.43
5. Step 5: Solve for x
   x = 865,612,144.43/42,993.84
6. Step 6: Final answer
   x = 20,133.40