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Finding the Fourth Proportional to 645.60, 890.36 and 521.22

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Solution

The fourth proportional to 645.60, 890.36 and 521.22 is: 718.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.60 : 890.36 = 521.22 : x
  2. Step 2: Convert to fraction form
    645.60/890.36 = 521.22/x
  3. Step 3: Cross multiply
    645.60x = 890.36 × 521.22
  4. Step 4: Simplify right side
    645.60x = 464,070.83
  5. Step 5: Solve for x
    x = 464,070.83/645.60
  6. Step 6: Final answer
    x = 718.82

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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.