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Finding the Fourth Proportional to 659.61, 987.05 and 485.87

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Solution

The fourth proportional to 659.61, 987.05 and 485.87 is: 727.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.61 : 987.05 = 485.87 : x
  2. Step 2: Convert to fraction form
    659.61/987.05 = 485.87/x
  3. Step 3: Cross multiply
    659.61x = 987.05 × 485.87
  4. Step 4: Simplify right side
    659.61x = 479,574.26
  5. Step 5: Solve for x
    x = 479,574.26/659.61
  6. Step 6: Final answer
    x = 727.06

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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.