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Finding the Fourth Proportional to 658.70, 988.74 and 485.56

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Solution

The fourth proportional to 658.70, 988.74 and 485.56 is: 728.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.70 : 988.74 = 485.56 : x
  2. Step 2: Convert to fraction form
    658.70/988.74 = 485.56/x
  3. Step 3: Cross multiply
    658.70x = 988.74 × 485.56
  4. Step 4: Simplify right side
    658.70x = 480,093.83
  5. Step 5: Solve for x
    x = 480,093.83/658.70
  6. Step 6: Final answer
    x = 728.85

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.