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Finding the Fourth Proportional to 645.86, 969.46 and 402.55

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Solution

The fourth proportional to 645.86, 969.46 and 402.55 is: 604.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.86 : 969.46 = 402.55 : x
  2. Step 2: Convert to fraction form
    645.86/969.46 = 402.55/x
  3. Step 3: Cross multiply
    645.86x = 969.46 × 402.55
  4. Step 4: Simplify right side
    645.86x = 390,256.12
  5. Step 5: Solve for x
    x = 390,256.12/645.86
  6. Step 6: Final answer
    x = 604.25

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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.