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Finding the Fourth Proportional to 380.98, 571.12 and 278.76

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Solution

The fourth proportional to 380.98, 571.12 and 278.76 is: 417.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.98 : 571.12 = 278.76 : x
  2. Step 2: Convert to fraction form
    380.98/571.12 = 278.76/x
  3. Step 3: Cross multiply
    380.98x = 571.12 × 278.76
  4. Step 4: Simplify right side
    380.98x = 159,205.41
  5. Step 5: Solve for x
    x = 159,205.41/380.98
  6. Step 6: Final answer
    x = 417.88

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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.