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Finding the Fourth Proportional to 319.81, 479.49 and 287.41

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Solution

The fourth proportional to 319.81, 479.49 and 287.41 is: 430.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.81 : 479.49 = 287.41 : x
  2. Step 2: Convert to fraction form
    319.81/479.49 = 287.41/x
  3. Step 3: Cross multiply
    319.81x = 479.49 × 287.41
  4. Step 4: Simplify right side
    319.81x = 137,810.22
  5. Step 5: Solve for x
    x = 137,810.22/319.81
  6. Step 6: Final answer
    x = 430.91

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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.