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Finding the Fourth Proportional to 479.78, 719.26 and 287

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Solution

The fourth proportional to 479.78, 719.26 and 287 is: 430.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.78 : 719.26 = 287 : x
  2. Step 2: Convert to fraction form
    479.78/719.26 = 287/x
  3. Step 3: Cross multiply
    479.78x = 719.26 × 287
  4. Step 4: Simplify right side
    479.78x = 206,427.62
  5. Step 5: Solve for x
    x = 206,427.62/479.78
  6. Step 6: Final answer
    x = 430.25

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.