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Finding the Fourth Proportional to 498.39, 687.94 and 288.61

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Solution

The fourth proportional to 498.39, 687.94 and 288.61 is: 398.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.39 : 687.94 = 288.61 : x
  2. Step 2: Convert to fraction form
    498.39/687.94 = 288.61/x
  3. Step 3: Cross multiply
    498.39x = 687.94 × 288.61
  4. Step 4: Simplify right side
    498.39x = 198,546.36
  5. Step 5: Solve for x
    x = 198,546.36/498.39
  6. Step 6: Final answer
    x = 398.38

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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.