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Finding the Fourth Proportional to 645.32, 891.04 and 396.74

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Solution

The fourth proportional to 645.32, 891.04 and 396.74 is: 547.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.32 : 891.04 = 396.74 : x
  2. Step 2: Convert to fraction form
    645.32/891.04 = 396.74/x
  3. Step 3: Cross multiply
    645.32x = 891.04 × 396.74
  4. Step 4: Simplify right side
    645.32x = 353,512.45
  5. Step 5: Solve for x
    x = 353,512.45/645.32
  6. Step 6: Final answer
    x = 547.81

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.