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Finding the Fourth Proportional to 498.49, 687.63 and 405.34

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Solution

The fourth proportional to 498.49, 687.63 and 405.34 is: 559.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.49 : 687.63 = 405.34 : x
  2. Step 2: Convert to fraction form
    498.49/687.63 = 405.34/x
  3. Step 3: Cross multiply
    498.49x = 687.63 × 405.34
  4. Step 4: Simplify right side
    498.49x = 278,723.94
  5. Step 5: Solve for x
    x = 278,723.94/498.49
  6. Step 6: Final answer
    x = 559.14

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.