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Finding the Fourth Proportional to 498.25, 687.41 and 288.39

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Solution

The fourth proportional to 498.25, 687.41 and 288.39 is: 397.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.25 : 687.41 = 288.39 : x
  2. Step 2: Convert to fraction form
    498.25/687.41 = 288.39/x
  3. Step 3: Cross multiply
    498.25x = 687.41 × 288.39
  4. Step 4: Simplify right side
    498.25x = 198,242.17
  5. Step 5: Solve for x
    x = 198,242.17/498.25
  6. Step 6: Final answer
    x = 397.88

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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.