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Finding the Fourth Proportional to 642.16, 963.28 and 257.44

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Solution

The fourth proportional to 642.16, 963.28 and 257.44 is: 386.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.16 : 963.28 = 257.44 : x
  2. Step 2: Convert to fraction form
    642.16/963.28 = 257.44/x
  3. Step 3: Cross multiply
    642.16x = 963.28 × 257.44
  4. Step 4: Simplify right side
    642.16x = 247,986.80
  5. Step 5: Solve for x
    x = 247,986.80/642.16
  6. Step 6: Final answer
    x = 386.18

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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.