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Finding the Fourth Proportional to 427.81, 642.48 and 393.51

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Solution

The fourth proportional to 427.81, 642.48 and 393.51 is: 590.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.81 : 642.48 = 393.51 : x
  2. Step 2: Convert to fraction form
    427.81/642.48 = 393.51/x
  3. Step 3: Cross multiply
    427.81x = 642.48 × 393.51
  4. Step 4: Simplify right side
    427.81x = 252,822.30
  5. Step 5: Solve for x
    x = 252,822.30/427.81
  6. Step 6: Final answer
    x = 590.97

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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.