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Finding the Fourth Proportional to 403.62, 556.65 and 287.70

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Solution

The fourth proportional to 403.62, 556.65 and 287.70 is: 396.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.62 : 556.65 = 287.70 : x
  2. Step 2: Convert to fraction form
    403.62/556.65 = 287.70/x
  3. Step 3: Cross multiply
    403.62x = 556.65 × 287.70
  4. Step 4: Simplify right side
    403.62x = 160,148.21
  5. Step 5: Solve for x
    x = 160,148.21/403.62
  6. Step 6: Final answer
    x = 396.78

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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.