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Finding the Fourth Proportional to 498.15, 687.23 and 311.57

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Solution

The fourth proportional to 498.15, 687.23 and 311.57 is: 429.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.15 : 687.23 = 311.57 : x
  2. Step 2: Convert to fraction form
    498.15/687.23 = 311.57/x
  3. Step 3: Cross multiply
    498.15x = 687.23 × 311.57
  4. Step 4: Simplify right side
    498.15x = 214,122.69
  5. Step 5: Solve for x
    x = 214,122.69/498.15
  6. Step 6: Final answer
    x = 429.84

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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.