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Finding the Fourth Proportional to 439.79, 661.23 and 427.49

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Solution

The fourth proportional to 439.79, 661.23 and 427.49 is: 642.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    439.79 : 661.23 = 427.49 : x
  2. Step 2: Convert to fraction form
    439.79/661.23 = 427.49/x
  3. Step 3: Cross multiply
    439.79x = 661.23 × 427.49
  4. Step 4: Simplify right side
    439.79x = 282,667.51
  5. Step 5: Solve for x
    x = 282,667.51/439.79
  6. Step 6: Final answer
    x = 642.73

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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.