Finding the Fourth Proportional to 1,137.50, 1,705.22 and 406.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,137.50 : 1,705.22 = 406.91 : x
2. Step 2: Convert to fraction form
   1,137.50/1,705.22 = 406.91/x
3. Step 3: Cross multiply
   1,137.50x = 1,705.22 × 406.91
4. Step 4: Simplify right side
   1,137.50x = 693,860.51
5. Step 5: Solve for x
   x = 693,860.51/1,137.50
6. Step 6: Final answer
   x = 609.99