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Finding the Fourth Proportional to 645.32, 890.51 and 379.81

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Solution

The fourth proportional to 645.32, 890.51 and 379.81 is: 524.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.32 : 890.51 = 379.81 : x
  2. Step 2: Convert to fraction form
    645.32/890.51 = 379.81/x
  3. Step 3: Cross multiply
    645.32x = 890.51 × 379.81
  4. Step 4: Simplify right side
    645.32x = 338,224.60
  5. Step 5: Solve for x
    x = 338,224.60/645.32
  6. Step 6: Final answer
    x = 524.12

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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.