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Finding the Fourth Proportional to 499.95, 689.94 and 278.91

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Solution

The fourth proportional to 499.95, 689.94 and 278.91 is: 384.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.95 : 689.94 = 278.91 : x
  2. Step 2: Convert to fraction form
    499.95/689.94 = 278.91/x
  3. Step 3: Cross multiply
    499.95x = 689.94 × 278.91
  4. Step 4: Simplify right side
    499.95x = 192,431.17
  5. Step 5: Solve for x
    x = 192,431.17/499.95
  6. Step 6: Final answer
    x = 384.90

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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.