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Finding the Fourth Proportional to 498.70, 688.46 and 312.30

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Solution

The fourth proportional to 498.70, 688.46 and 312.30 is: 431.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.70 : 688.46 = 312.30 : x
  2. Step 2: Convert to fraction form
    498.70/688.46 = 312.30/x
  3. Step 3: Cross multiply
    498.70x = 688.46 × 312.30
  4. Step 4: Simplify right side
    498.70x = 215,006.06
  5. Step 5: Solve for x
    x = 215,006.06/498.70
  6. Step 6: Final answer
    x = 431.13

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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.