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Finding the Fourth Proportional to 499.47, 689.27 and 278.43

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Solution

The fourth proportional to 499.47, 689.27 and 278.43 is: 384.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.47 : 689.27 = 278.43 : x
  2. Step 2: Convert to fraction form
    499.47/689.27 = 278.43/x
  3. Step 3: Cross multiply
    499.47x = 689.27 × 278.43
  4. Step 4: Simplify right side
    499.47x = 191,913.45
  5. Step 5: Solve for x
    x = 191,913.45/499.47
  6. Step 6: Final answer
    x = 384.23

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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.