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Finding the Fourth Proportional to 409.56, 611.81 and 328.56

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Solution

The fourth proportional to 409.56, 611.81 and 328.56 is: 490.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    409.56 : 611.81 = 328.56 : x
  2. Step 2: Convert to fraction form
    409.56/611.81 = 328.56/x
  3. Step 3: Cross multiply
    409.56x = 611.81 × 328.56
  4. Step 4: Simplify right side
    409.56x = 201,014.65
  5. Step 5: Solve for x
    x = 201,014.65/409.56
  6. Step 6: Final answer
    x = 490.81

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.