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Finding the Fourth Proportional to 661.80, 992.59 and 387.62

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Solution

The fourth proportional to 661.80, 992.59 and 387.62 is: 581.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.80 : 992.59 = 387.62 : x
  2. Step 2: Convert to fraction form
    661.80/992.59 = 387.62/x
  3. Step 3: Cross multiply
    661.80x = 992.59 × 387.62
  4. Step 4: Simplify right side
    661.80x = 384,745.53
  5. Step 5: Solve for x
    x = 384,745.53/661.80
  6. Step 6: Final answer
    x = 581.36

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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.