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Finding the Fourth Proportional to 389.36, 536.88 and 278.79

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Solution

The fourth proportional to 389.36, 536.88 and 278.79 is: 384.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.36 : 536.88 = 278.79 : x
  2. Step 2: Convert to fraction form
    389.36/536.88 = 278.79/x
  3. Step 3: Cross multiply
    389.36x = 536.88 × 278.79
  4. Step 4: Simplify right side
    389.36x = 149,676.78
  5. Step 5: Solve for x
    x = 149,676.78/389.36
  6. Step 6: Final answer
    x = 384.42

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.