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Finding the Fourth Proportional to 652.50, 978.96 and 408.72

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Solution

The fourth proportional to 652.50, 978.96 and 408.72 is: 613.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    652.50 : 978.96 = 408.72 : x
  2. Step 2: Convert to fraction form
    652.50/978.96 = 408.72/x
  3. Step 3: Cross multiply
    652.50x = 978.96 × 408.72
  4. Step 4: Simplify right side
    652.50x = 400,120.53
  5. Step 5: Solve for x
    x = 400,120.53/652.50
  6. Step 6: Final answer
    x = 613.21

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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.