Finding the Fourth Proportional to 78,648.42, 117,971.91 and 31,890.18

Step by Step Solution

1. Step 1: Write the proportion equation
   78,648.42 : 117,971.91 = 31,890.18 : x
2. Step 2: Convert to fraction form
   78,648.42/117,971.91 = 31,890.18/x
3. Step 3: Cross multiply
   78,648.42x = 117,971.91 × 31,890.18
4. Step 4: Simplify right side
   78,648.42x = 3,762,145,444.84
5. Step 5: Solve for x
   x = 3,762,145,444.84/78,648.42
6. Step 6: Final answer
   x = 47,834.98