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Finding the Fourth Proportional to 499.75, 689.64 and 278.69

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Solution

The fourth proportional to 499.75, 689.64 and 278.69 is: 384.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.75 : 689.64 = 278.69 : x
  2. Step 2: Convert to fraction form
    499.75/689.64 = 278.69/x
  3. Step 3: Cross multiply
    499.75x = 689.64 × 278.69
  4. Step 4: Simplify right side
    499.75x = 192,195.77
  5. Step 5: Solve for x
    x = 192,195.77/499.75
  6. Step 6: Final answer
    x = 384.59

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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.