Finding the Fourth Proportional to 42,886.65, 64,341.51 and 17,918.40

Step by Step Solution

1. Step 1: Write the proportion equation
   42,886.65 : 64,341.51 = 17,918.40 : x
2. Step 2: Convert to fraction form
   42,886.65/64,341.51 = 17,918.40/x
3. Step 3: Cross multiply
   42,886.65x = 64,341.51 × 17,918.40
4. Step 4: Simplify right side
   42,886.65x = 1,152,896,912.78
5. Step 5: Solve for x
   x = 1,152,896,912.78/42,886.65
6. Step 6: Final answer
   x = 26,882.42