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Finding the Fourth Proportional to 658.80, 988.69 and 412.36

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Solution

The fourth proportional to 658.80, 988.69 and 412.36 is: 618.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.80 : 988.69 = 412.36 : x
  2. Step 2: Convert to fraction form
    658.80/988.69 = 412.36/x
  3. Step 3: Cross multiply
    658.80x = 988.69 × 412.36
  4. Step 4: Simplify right side
    658.80x = 407,693.48
  5. Step 5: Solve for x
    x = 407,693.48/658.80
  6. Step 6: Final answer
    x = 618.84

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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.