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Finding the Fourth Proportional to 839.91, 1,260.60 and 401.70

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Solution

The fourth proportional to 839.91, 1,260.60 and 401.70 is: 602.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    839.91 : 1,260.60 = 401.70 : x
  2. Step 2: Convert to fraction form
    839.91/1,260.60 = 401.70/x
  3. Step 3: Cross multiply
    839.91x = 1,260.60 × 401.70
  4. Step 4: Simplify right side
    839.91x = 506,383.02
  5. Step 5: Solve for x
    x = 506,383.02/839.91
  6. Step 6: Final answer
    x = 602.90

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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.