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Finding the Fourth Proportional to 311.80, 429.72 and 302.92

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Solution

The fourth proportional to 311.80, 429.72 and 302.92 is: 417.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.80 : 429.72 = 302.92 : x
  2. Step 2: Convert to fraction form
    311.80/429.72 = 302.92/x
  3. Step 3: Cross multiply
    311.80x = 429.72 × 302.92
  4. Step 4: Simplify right side
    311.80x = 130,170.78
  5. Step 5: Solve for x
    x = 130,170.78/311.80
  6. Step 6: Final answer
    x = 417.48

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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.