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Finding the Fourth Proportional to 638.24, 880.40 and 402.16

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Solution

The fourth proportional to 638.24, 880.40 and 402.16 is: 554.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.24 : 880.40 = 402.16 : x
  2. Step 2: Convert to fraction form
    638.24/880.40 = 402.16/x
  3. Step 3: Cross multiply
    638.24x = 880.40 × 402.16
  4. Step 4: Simplify right side
    638.24x = 354,061.66
  5. Step 5: Solve for x
    x = 354,061.66/638.24
  6. Step 6: Final answer
    x = 554.75

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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.