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Finding the Fourth Proportional to 643.05, 966.02 and 618.75

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Solution

The fourth proportional to 643.05, 966.02 and 618.75 is: 929.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.05 : 966.02 = 618.75 : x
  2. Step 2: Convert to fraction form
    643.05/966.02 = 618.75/x
  3. Step 3: Cross multiply
    643.05x = 966.02 × 618.75
  4. Step 4: Simplify right side
    643.05x = 597,721.78
  5. Step 5: Solve for x
    x = 597,721.78/643.05
  6. Step 6: Final answer
    x = 929.51

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Double scale
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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.