Finding the Fourth Proportional to 2,142, 3,212.18 and 842.76

Step by Step Solution

1. Step 1: Write the proportion equation
   2,142 : 3,212.18 = 842.76 : x
2. Step 2: Convert to fraction form
   2,142/3,212.18 = 842.76/x
3. Step 3: Cross multiply
   2,142x = 3,212.18 × 842.76
4. Step 4: Simplify right side
   2,142x = 2,707,096.82
5. Step 5: Solve for x
   x = 2,707,096.82/2,142
6. Step 6: Final answer
   x = 1,263.82