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Finding the Fourth Proportional to 651.20, 904.70 and 645.20

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Solution

The fourth proportional to 651.20, 904.70 and 645.20 is: 896.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.20 : 904.70 = 645.20 : x
  2. Step 2: Convert to fraction form
    651.20/904.70 = 645.20/x
  3. Step 3: Cross multiply
    651.20x = 904.70 × 645.20
  4. Step 4: Simplify right side
    651.20x = 583,712.44
  5. Step 5: Solve for x
    x = 583,712.44/651.20
  6. Step 6: Final answer
    x = 896.36

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.