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Finding the Fourth Proportional to 801.90, 1,202.76 and 390.84

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Solution

The fourth proportional to 801.90, 1,202.76 and 390.84 is: 586.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    801.90 : 1,202.76 = 390.84 : x
  2. Step 2: Convert to fraction form
    801.90/1,202.76 = 390.84/x
  3. Step 3: Cross multiply
    801.90x = 1,202.76 × 390.84
  4. Step 4: Simplify right side
    801.90x = 470,086.72
  5. Step 5: Solve for x
    x = 470,086.72/801.90
  6. Step 6: Final answer
    x = 586.22

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.