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Finding the Fourth Proportional to 898.60, 1,348.81 and 638.90

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Solution

The fourth proportional to 898.60, 1,348.81 and 638.90 is: 958.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    898.60 : 1,348.81 = 638.90 : x
  2. Step 2: Convert to fraction form
    898.60/1,348.81 = 638.90/x
  3. Step 3: Cross multiply
    898.60x = 1,348.81 × 638.90
  4. Step 4: Simplify right side
    898.60x = 861,746.37
  5. Step 5: Solve for x
    x = 861,746.37/898.60
  6. Step 6: Final answer
    x = 958.99

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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.