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Finding the Fourth Proportional to 638.95, 959.53 and 380.58

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Solution

The fourth proportional to 638.95, 959.53 and 380.58 is: 571.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.95 : 959.53 = 380.58 : x
  2. Step 2: Convert to fraction form
    638.95/959.53 = 380.58/x
  3. Step 3: Cross multiply
    638.95x = 959.53 × 380.58
  4. Step 4: Simplify right side
    638.95x = 365,177.93
  5. Step 5: Solve for x
    x = 365,177.93/638.95
  6. Step 6: Final answer
    x = 571.53

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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.