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Finding the Fourth Proportional to 661.59, 992.57 and 387.77

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Solution

The fourth proportional to 661.59, 992.57 and 387.77 is: 581.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.59 : 992.57 = 387.77 : x
  2. Step 2: Convert to fraction form
    661.59/992.57 = 387.77/x
  3. Step 3: Cross multiply
    661.59x = 992.57 × 387.77
  4. Step 4: Simplify right side
    661.59x = 384,881.97
  5. Step 5: Solve for x
    x = 384,881.97/661.59
  6. Step 6: Final answer
    x = 581.75

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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.