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Finding the Fourth Proportional to 389.31, 536.72 and 284.19

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Solution

The fourth proportional to 389.31, 536.72 and 284.19 is: 391.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.31 : 536.72 = 284.19 : x
  2. Step 2: Convert to fraction form
    389.31/536.72 = 284.19/x
  3. Step 3: Cross multiply
    389.31x = 536.72 × 284.19
  4. Step 4: Simplify right side
    389.31x = 152,529.04
  5. Step 5: Solve for x
    x = 152,529.04/389.31
  6. Step 6: Final answer
    x = 391.79

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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.