Finding the Fourth Proportional to 93,870, 129,540.68 and 51,428.72

Step by Step Solution

1. Step 1: Write the proportion equation
   93,870 : 129,540.68 = 51,428.72 : x
2. Step 2: Convert to fraction form
   93,870/129,540.68 = 51,428.72/x
3. Step 3: Cross multiply
   93,870x = 129,540.68 × 51,428.72
4. Step 4: Simplify right side
   93,870x = 6,662,111,360.33
5. Step 5: Solve for x
   x = 6,662,111,360.33/93,870
6. Step 6: Final answer
   x = 70,971.68