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Finding the Fourth Proportional to 649.81, 974.36 and 390.11

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Solution

The fourth proportional to 649.81, 974.36 and 390.11 is: 584.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.81 : 974.36 = 390.11 : x
  2. Step 2: Convert to fraction form
    649.81/974.36 = 390.11/x
  3. Step 3: Cross multiply
    649.81x = 974.36 × 390.11
  4. Step 4: Simplify right side
    649.81x = 380,103.68
  5. Step 5: Solve for x
    x = 380,103.68/649.81
  6. Step 6: Final answer
    x = 584.94

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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.