Finding the Fourth Proportional to 291,061.35, 401,448.15 and 257,009.76

Step by Step Solution

1. Step 1: Write the proportion equation
   291,061.35 : 401,448.15 = 257,009.76 : x
2. Step 2: Convert to fraction form
   291,061.35/401,448.15 = 257,009.76/x
3. Step 3: Cross multiply
   291,061.35x = 401,448.15 × 257,009.76
4. Step 4: Simplify right side
   291,061.35x = 103,176,092,683.94
5. Step 5: Solve for x
   x = 103,176,092,683.94/291,061.35
6. Step 6: Final answer
   x = 354,482.29