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Finding the Fourth Proportional to 312.80, 469.29 and 137.12

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Solution

The fourth proportional to 312.80, 469.29 and 137.12 is: 205.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.80 : 469.29 = 137.12 : x
  2. Step 2: Convert to fraction form
    312.80/469.29 = 137.12/x
  3. Step 3: Cross multiply
    312.80x = 469.29 × 137.12
  4. Step 4: Simplify right side
    312.80x = 64,348.36
  5. Step 5: Solve for x
    x = 64,348.36/312.80
  6. Step 6: Final answer
    x = 205.72

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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.