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Finding the Fourth Proportional to 499.42, 689.15 and 278.35

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Solution

The fourth proportional to 499.42, 689.15 and 278.35 is: 384.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.42 : 689.15 = 278.35 : x
  2. Step 2: Convert to fraction form
    499.42/689.15 = 278.35/x
  3. Step 3: Cross multiply
    499.42x = 689.15 × 278.35
  4. Step 4: Simplify right side
    499.42x = 191,821.46
  5. Step 5: Solve for x
    x = 191,821.46/499.42
  6. Step 6: Final answer
    x = 384.09

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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.