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Finding the Fourth Proportional to 643.51, 966.81 and 412.86

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Solution

The fourth proportional to 643.51, 966.81 and 412.86 is: 620.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.51 : 966.81 = 412.86 : x
  2. Step 2: Convert to fraction form
    643.51/966.81 = 412.86/x
  3. Step 3: Cross multiply
    643.51x = 966.81 × 412.86
  4. Step 4: Simplify right side
    643.51x = 399,151.31
  5. Step 5: Solve for x
    x = 399,151.31/643.51
  6. Step 6: Final answer
    x = 620.27

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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.