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Finding the Fourth Proportional to 659.21, 987.39 and 494.51

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Solution

The fourth proportional to 659.21, 987.39 and 494.51 is: 740.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.21 : 987.39 = 494.51 : x
  2. Step 2: Convert to fraction form
    659.21/987.39 = 494.51/x
  3. Step 3: Cross multiply
    659.21x = 987.39 × 494.51
  4. Step 4: Simplify right side
    659.21x = 488,269.29
  5. Step 5: Solve for x
    x = 488,269.29/659.21
  6. Step 6: Final answer
    x = 740.69

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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.