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Finding the Fourth Proportional to 642.48, 965.31 and 411.47

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Solution

The fourth proportional to 642.48, 965.31 and 411.47 is: 618.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.48 : 965.31 = 411.47 : x
  2. Step 2: Convert to fraction form
    642.48/965.31 = 411.47/x
  3. Step 3: Cross multiply
    642.48x = 965.31 × 411.47
  4. Step 4: Simplify right side
    642.48x = 397,194.05
  5. Step 5: Solve for x
    x = 397,194.05/642.48
  6. Step 6: Final answer
    x = 618.22

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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.