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Finding the Fourth Proportional to 312.85, 469.28 and 130.30

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Solution

The fourth proportional to 312.85, 469.28 and 130.30 is: 195.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.85 : 469.28 = 130.30 : x
  2. Step 2: Convert to fraction form
    312.85/469.28 = 130.30/x
  3. Step 3: Cross multiply
    312.85x = 469.28 × 130.30
  4. Step 4: Simplify right side
    312.85x = 61,147.18
  5. Step 5: Solve for x
    x = 61,147.18/312.85
  6. Step 6: Final answer
    x = 195.45

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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.