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Finding the Fourth Proportional to 442.80, 611.22 and 311.88

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Solution

The fourth proportional to 442.80, 611.22 and 311.88 is: 430.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    442.80 : 611.22 = 311.88 : x
  2. Step 2: Convert to fraction form
    442.80/611.22 = 311.88/x
  3. Step 3: Cross multiply
    442.80x = 611.22 × 311.88
  4. Step 4: Simplify right side
    442.80x = 190,627.29
  5. Step 5: Solve for x
    x = 190,627.29/442.80
  6. Step 6: Final answer
    x = 430.50

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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.