Finding the Fourth Proportional to 11,870.23, 16,384.32 and 7,840

Step by Step Solution

1. Step 1: Write the proportion equation
   11,870.23 : 16,384.32 = 7,840 : x
2. Step 2: Convert to fraction form
   11,870.23/16,384.32 = 7,840/x
3. Step 3: Cross multiply
   11,870.23x = 16,384.32 × 7,840
4. Step 4: Simplify right side
   11,870.23x = 128,453,068.80
5. Step 5: Solve for x
   x = 128,453,068.80/11,870.23
6. Step 6: Final answer
   x = 10,821.45