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Finding the Fourth Proportional to 649.28, 974.12 and 278.89

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Solution

The fourth proportional to 649.28, 974.12 and 278.89 is: 418.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.28 : 974.12 = 278.89 : x
  2. Step 2: Convert to fraction form
    649.28/974.12 = 278.89/x
  3. Step 3: Cross multiply
    649.28x = 974.12 × 278.89
  4. Step 4: Simplify right side
    649.28x = 271,668.50
  5. Step 5: Solve for x
    x = 271,668.50/649.28
  6. Step 6: Final answer
    x = 418.41

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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.