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Finding the Fourth Proportional to 389.43, 536.78 and 319.37

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Solution

The fourth proportional to 389.43, 536.78 and 319.37 is: 440.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.43 : 536.78 = 319.37 : x
  2. Step 2: Convert to fraction form
    389.43/536.78 = 319.37/x
  3. Step 3: Cross multiply
    389.43x = 536.78 × 319.37
  4. Step 4: Simplify right side
    389.43x = 171,429.54
  5. Step 5: Solve for x
    x = 171,429.54/389.43
  6. Step 6: Final answer
    x = 440.21

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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.