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Finding the Fourth Proportional to 499.41, 689.20 and 278.42

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Solution

The fourth proportional to 499.41, 689.20 and 278.42 is: 384.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.41 : 689.20 = 278.42 : x
  2. Step 2: Convert to fraction form
    499.41/689.20 = 278.42/x
  3. Step 3: Cross multiply
    499.41x = 689.20 × 278.42
  4. Step 4: Simplify right side
    499.41x = 191,883.62
  5. Step 5: Solve for x
    x = 191,883.62/499.41
  6. Step 6: Final answer
    x = 384.22

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.