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Finding the Fourth Proportional to 389.81, 536.77 and 279.09

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Solution

The fourth proportional to 389.81, 536.77 and 279.09 is: 384.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.81 : 536.77 = 279.09 : x
  2. Step 2: Convert to fraction form
    389.81/536.77 = 279.09/x
  3. Step 3: Cross multiply
    389.81x = 536.77 × 279.09
  4. Step 4: Simplify right side
    389.81x = 149,807.14
  5. Step 5: Solve for x
    x = 149,807.14/389.81
  6. Step 6: Final answer
    x = 384.31

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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.