Finding the Fourth Proportional to 42,985.60, 64,402.10 and 17,970.50

Step by Step Solution

1. Step 1: Write the proportion equation
   42,985.60 : 64,402.10 = 17,970.50 : x
2. Step 2: Convert to fraction form
   42,985.60/64,402.10 = 17,970.50/x
3. Step 3: Cross multiply
   42,985.60x = 64,402.10 × 17,970.50
4. Step 4: Simplify right side
   42,985.60x = 1,157,337,938.05
5. Step 5: Solve for x
   x = 1,157,337,938.05/42,985.60
6. Step 6: Final answer
   x = 26,923.85