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Finding the Fourth Proportional to 642.60, 969.03 and 638.28

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Solution

The fourth proportional to 642.60, 969.03 and 638.28 is: 962.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.60 : 969.03 = 638.28 : x
  2. Step 2: Convert to fraction form
    642.60/969.03 = 638.28/x
  3. Step 3: Cross multiply
    642.60x = 969.03 × 638.28
  4. Step 4: Simplify right side
    642.60x = 618,512.47
  5. Step 5: Solve for x
    x = 618,512.47/642.60
  6. Step 6: Final answer
    x = 962.52

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.