Finding the Fourth Proportional to 37,905.90, 52,312.72 and 21,990.35

Step by Step Solution

1. Step 1: Write the proportion equation
   37,905.90 : 52,312.72 = 21,990.35 : x
2. Step 2: Convert to fraction form
   37,905.90/52,312.72 = 21,990.35/x
3. Step 3: Cross multiply
   37,905.90x = 52,312.72 × 21,990.35
4. Step 4: Simplify right side
   37,905.90x = 1,150,374,788.18
5. Step 5: Solve for x
   x = 1,150,374,788.18/37,905.90
6. Step 6: Final answer
   x = 30,348.18