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Finding the Fourth Proportional to 645.64, 890.18 and 383.56

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Solution

The fourth proportional to 645.64, 890.18 and 383.56 is: 528.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.64 : 890.18 = 383.56 : x
  2. Step 2: Convert to fraction form
    645.64/890.18 = 383.56/x
  3. Step 3: Cross multiply
    645.64x = 890.18 × 383.56
  4. Step 4: Simplify right side
    645.64x = 341,437.44
  5. Step 5: Solve for x
    x = 341,437.44/645.64
  6. Step 6: Final answer
    x = 528.84

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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.