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Finding the Fourth Proportional to 652.89, 900.81 and 420.15

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Solution

The fourth proportional to 652.89, 900.81 and 420.15 is: 579.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    652.89 : 900.81 = 420.15 : x
  2. Step 2: Convert to fraction form
    652.89/900.81 = 420.15/x
  3. Step 3: Cross multiply
    652.89x = 900.81 × 420.15
  4. Step 4: Simplify right side
    652.89x = 378,475.32
  5. Step 5: Solve for x
    x = 378,475.32/652.89
  6. Step 6: Final answer
    x = 579.69

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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.