Finding the Fourth Proportional to 9,912, 14,859.72 and 4,072.80

Step by Step Solution

1. Step 1: Write the proportion equation
   9,912 : 14,859.72 = 4,072.80 : x
2. Step 2: Convert to fraction form
   9,912/14,859.72 = 4,072.80/x
3. Step 3: Cross multiply
   9,912x = 14,859.72 × 4,072.80
4. Step 4: Simplify right side
   9,912x = 60,520,667.62
5. Step 5: Solve for x
   x = 60,520,667.62/9,912
6. Step 6: Final answer
   x = 6,105.80