Finding the Fourth Proportional to 42,759.55, 64,145.40 and 13,174.30

Step by Step Solution

1. Step 1: Write the proportion equation
   42,759.55 : 64,145.40 = 13,174.30 : x
2. Step 2: Convert to fraction form
   42,759.55/64,145.40 = 13,174.30/x
3. Step 3: Cross multiply
   42,759.55x = 64,145.40 × 13,174.30
4. Step 4: Simplify right side
   42,759.55x = 845,070,743.22
5. Step 5: Solve for x
   x = 845,070,743.22/42,759.55
6. Step 6: Final answer
   x = 19,763.32