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Finding the Fourth Proportional to 645.77, 891.20 and 380.22

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Solution

The fourth proportional to 645.77, 891.20 and 380.22 is: 524.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.77 : 891.20 = 380.22 : x
  2. Step 2: Convert to fraction form
    645.77/891.20 = 380.22/x
  3. Step 3: Cross multiply
    645.77x = 891.20 × 380.22
  4. Step 4: Simplify right side
    645.77x = 338,853.01
  5. Step 5: Solve for x
    x = 338,853.01/645.77
  6. Step 6: Final answer
    x = 524.73

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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.