Finding the Fourth Proportional to 7,870.50, 11,802.67 and 3,189.30

Step by Step Solution

1. Step 1: Write the proportion equation
   7,870.50 : 11,802.67 = 3,189.30 : x
2. Step 2: Convert to fraction form
   7,870.50/11,802.67 = 3,189.30/x
3. Step 3: Cross multiply
   7,870.50x = 11,802.67 × 3,189.30
4. Step 4: Simplify right side
   7,870.50x = 37,642,188.44
5. Step 5: Solve for x
   x = 37,642,188.44/7,870.50
6. Step 6: Final answer
   x = 4,782.70