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Finding the Fourth Proportional to 499.66, 689.45 and 278.57

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Solution

The fourth proportional to 499.66, 689.45 and 278.57 is: 384.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.66 : 689.45 = 278.57 : x
  2. Step 2: Convert to fraction form
    499.66/689.45 = 278.57/x
  3. Step 3: Cross multiply
    499.66x = 689.45 × 278.57
  4. Step 4: Simplify right side
    499.66x = 192,060.42
  5. Step 5: Solve for x
    x = 192,060.42/499.66
  6. Step 6: Final answer
    x = 384.38

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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.