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Finding the Fourth Proportional to 341.20, 509.09 and 287.20

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Solution

The fourth proportional to 341.20, 509.09 and 287.20 is: 428.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    341.20 : 509.09 = 287.20 : x
  2. Step 2: Convert to fraction form
    341.20/509.09 = 287.20/x
  3. Step 3: Cross multiply
    341.20x = 509.09 × 287.20
  4. Step 4: Simplify right side
    341.20x = 146,210.65
  5. Step 5: Solve for x
    x = 146,210.65/341.20
  6. Step 6: Final answer
    x = 428.52

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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.