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Finding the Fourth Proportional to 431.40, 645.58 and 269.16

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Solution

The fourth proportional to 431.40, 645.58 and 269.16 is: 402.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    431.40 : 645.58 = 269.16 : x
  2. Step 2: Convert to fraction form
    431.40/645.58 = 269.16/x
  3. Step 3: Cross multiply
    431.40x = 645.58 × 269.16
  4. Step 4: Simplify right side
    431.40x = 173,764.31
  5. Step 5: Solve for x
    x = 173,764.31/431.40
  6. Step 6: Final answer
    x = 402.79

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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.