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Finding the Fourth Proportional to 498.97, 688.61 and 289.20

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Solution

The fourth proportional to 498.97, 688.61 and 289.20 is: 399.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.97 : 688.61 = 289.20 : x
  2. Step 2: Convert to fraction form
    498.97/688.61 = 289.20/x
  3. Step 3: Cross multiply
    498.97x = 688.61 × 289.20
  4. Step 4: Simplify right side
    498.97x = 199,146.74
  5. Step 5: Solve for x
    x = 199,146.74/498.97
  6. Step 6: Final answer
    x = 399.12

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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.