Finding the Fourth Proportional to 15,870.15, 21,900.04 and 9,157.93

Step by Step Solution

1. Step 1: Write the proportion equation
   15,870.15 : 21,900.04 = 9,157.93 : x
2. Step 2: Convert to fraction form
   15,870.15/21,900.04 = 9,157.93/x
3. Step 3: Cross multiply
   15,870.15x = 21,900.04 × 9,157.93
4. Step 4: Simplify right side
   15,870.15x = 200,559,033.32
5. Step 5: Solve for x
   x = 200,559,033.32/15,870.15
6. Step 6: Final answer
   x = 12,637.50