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Finding the Fourth Proportional to 498.11, 687.40 and 288.29

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Solution

The fourth proportional to 498.11, 687.40 and 288.29 is: 397.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.11 : 687.40 = 288.29 : x
  2. Step 2: Convert to fraction form
    498.11/687.40 = 288.29/x
  3. Step 3: Cross multiply
    498.11x = 687.40 × 288.29
  4. Step 4: Simplify right side
    498.11x = 198,165.67
  5. Step 5: Solve for x
    x = 198,165.67/498.11
  6. Step 6: Final answer
    x = 397.84

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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.