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Finding the Fourth Proportional to 499.64, 689.60 and 289.85

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Solution

The fourth proportional to 499.64, 689.60 and 289.85 is: 400.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.64 : 689.60 = 289.85 : x
  2. Step 2: Convert to fraction form
    499.64/689.60 = 289.85/x
  3. Step 3: Cross multiply
    499.64x = 689.60 × 289.85
  4. Step 4: Simplify right side
    499.64x = 199,880.56
  5. Step 5: Solve for x
    x = 199,880.56/499.64
  6. Step 6: Final answer
    x = 400.05

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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.