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Finding the Fourth Proportional to 801.21, 1,201.57 and 430.79

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Solution

The fourth proportional to 801.21, 1,201.57 and 430.79 is: 646.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    801.21 : 1,201.57 = 430.79 : x
  2. Step 2: Convert to fraction form
    801.21/1,201.57 = 430.79/x
  3. Step 3: Cross multiply
    801.21x = 1,201.57 × 430.79
  4. Step 4: Simplify right side
    801.21x = 517,618.33
  5. Step 5: Solve for x
    x = 517,618.33/801.21
  6. Step 6: Final answer
    x = 646.05

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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.