Finding the Fourth Proportional to 42,870.96, 64,309.32 and 17,912.88

Step by Step Solution

1. Step 1: Write the proportion equation
   42,870.96 : 64,309.32 = 17,912.88 : x
2. Step 2: Convert to fraction form
   42,870.96/64,309.32 = 17,912.88/x
3. Step 3: Cross multiply
   42,870.96x = 64,309.32 × 17,912.88
4. Step 4: Simplify right side
   42,870.96x = 1,151,965,132.04
5. Step 5: Solve for x
   x = 1,151,965,132.04/42,870.96
6. Step 6: Final answer
   x = 26,870.52