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Finding the Fourth Proportional to 658.20, 988.86 and 657.18

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Solution

The fourth proportional to 658.20, 988.86 and 657.18 is: 987.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.20 : 988.86 = 657.18 : x
  2. Step 2: Convert to fraction form
    658.20/988.86 = 657.18/x
  3. Step 3: Cross multiply
    658.20x = 988.86 × 657.18
  4. Step 4: Simplify right side
    658.20x = 649,859.01
  5. Step 5: Solve for x
    x = 649,859.01/658.20
  6. Step 6: Final answer
    x = 987.33

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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.