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Finding the Fourth Proportional to 499.72, 689.65 and 289.95

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Solution

The fourth proportional to 499.72, 689.65 and 289.95 is: 400.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.72 : 689.65 = 289.95 : x
  2. Step 2: Convert to fraction form
    499.72/689.65 = 289.95/x
  3. Step 3: Cross multiply
    499.72x = 689.65 × 289.95
  4. Step 4: Simplify right side
    499.72x = 199,964.02
  5. Step 5: Solve for x
    x = 199,964.02/499.72
  6. Step 6: Final answer
    x = 400.15

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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.