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Finding the Fourth Proportional to 680.25, 1,020 and 402.72

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Solution

The fourth proportional to 680.25, 1,020 and 402.72 is: 603.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.25 : 1,020 = 402.72 : x
  2. Step 2: Convert to fraction form
    680.25/1,020 = 402.72/x
  3. Step 3: Cross multiply
    680.25x = 1,020 × 402.72
  4. Step 4: Simplify right side
    680.25x = 410,774.40
  5. Step 5: Solve for x
    x = 410,774.40/680.25
  6. Step 6: Final answer
    x = 603.86

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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.