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Finding the Fourth Proportional to 428.58, 645.21 and 292.49

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Solution

The fourth proportional to 428.58, 645.21 and 292.49 is: 440.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.58 : 645.21 = 292.49 : x
  2. Step 2: Convert to fraction form
    428.58/645.21 = 292.49/x
  3. Step 3: Cross multiply
    428.58x = 645.21 × 292.49
  4. Step 4: Simplify right side
    428.58x = 188,713.52
  5. Step 5: Solve for x
    x = 188,713.52/428.58
  6. Step 6: Final answer
    x = 440.33

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.