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Finding the Fourth Proportional to 663.55, 995.33 and 391.54

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Solution

The fourth proportional to 663.55, 995.33 and 391.54 is: 587.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.55 : 995.33 = 391.54 : x
  2. Step 2: Convert to fraction form
    663.55/995.33 = 391.54/x
  3. Step 3: Cross multiply
    663.55x = 995.33 × 391.54
  4. Step 4: Simplify right side
    663.55x = 389,711.51
  5. Step 5: Solve for x
    x = 389,711.51/663.55
  6. Step 6: Final answer
    x = 587.31

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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.