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Finding the Fourth Proportional to 499.78, 689.58 and 303.30

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Solution

The fourth proportional to 499.78, 689.58 and 303.30 is: 418.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.78 : 689.58 = 303.30 : x
  2. Step 2: Convert to fraction form
    499.78/689.58 = 303.30/x
  3. Step 3: Cross multiply
    499.78x = 689.58 × 303.30
  4. Step 4: Simplify right side
    499.78x = 209,149.61
  5. Step 5: Solve for x
    x = 209,149.61/499.78
  6. Step 6: Final answer
    x = 418.48

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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.