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Finding the Fourth Proportional to 659.10, 987.20 and 384.90

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Solution

The fourth proportional to 659.10, 987.20 and 384.90 is: 576.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.10 : 987.20 = 384.90 : x
  2. Step 2: Convert to fraction form
    659.10/987.20 = 384.90/x
  3. Step 3: Cross multiply
    659.10x = 987.20 × 384.90
  4. Step 4: Simplify right side
    659.10x = 379,971.36
  5. Step 5: Solve for x
    x = 379,971.36/659.10
  6. Step 6: Final answer
    x = 576.50

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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.