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Finding the Fourth Proportional to 643.42, 966.30 and 400.42

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Solution

The fourth proportional to 643.42, 966.30 and 400.42 is: 601.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.42 : 966.30 = 400.42 : x
  2. Step 2: Convert to fraction form
    643.42/966.30 = 400.42/x
  3. Step 3: Cross multiply
    643.42x = 966.30 × 400.42
  4. Step 4: Simplify right side
    643.42x = 386,925.85
  5. Step 5: Solve for x
    x = 386,925.85/643.42
  6. Step 6: Final answer
    x = 601.36

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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.