Finding the Fourth Proportional to 1,068.38, 1,602.42 and 419.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,068.38 : 1,602.42 = 419.30 : x
2. Step 2: Convert to fraction form
   1,068.38/1,602.42 = 419.30/x
3. Step 3: Cross multiply
   1,068.38x = 1,602.42 × 419.30
4. Step 4: Simplify right side
   1,068.38x = 671,894.71
5. Step 5: Solve for x
   x = 671,894.71/1,068.38
6. Step 6: Final answer
   x = 628.89