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Finding the Fourth Proportional to 319.50, 440.91 and 287.10

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Solution

The fourth proportional to 319.50, 440.91 and 287.10 is: 396.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.50 : 440.91 = 287.10 : x
  2. Step 2: Convert to fraction form
    319.50/440.91 = 287.10/x
  3. Step 3: Cross multiply
    319.50x = 440.91 × 287.10
  4. Step 4: Simplify right side
    319.50x = 126,585.26
  5. Step 5: Solve for x
    x = 126,585.26/319.50
  6. Step 6: Final answer
    x = 396.20

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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.