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Finding the Fourth Proportional to 498.90, 688.14 and 405.64

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Solution

The fourth proportional to 498.90, 688.14 and 405.64 is: 559.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.90 : 688.14 = 405.64 : x
  2. Step 2: Convert to fraction form
    498.90/688.14 = 405.64/x
  3. Step 3: Cross multiply
    498.90x = 688.14 × 405.64
  4. Step 4: Simplify right side
    498.90x = 279,137.11
  5. Step 5: Solve for x
    x = 279,137.11/498.90
  6. Step 6: Final answer
    x = 559.51

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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.