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Finding the Fourth Proportional to 312.80, 469.28 and 158.72

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Solution

The fourth proportional to 312.80, 469.28 and 158.72 is: 238.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.80 : 469.28 = 158.72 : x
  2. Step 2: Convert to fraction form
    312.80/469.28 = 158.72/x
  3. Step 3: Cross multiply
    312.80x = 469.28 × 158.72
  4. Step 4: Simplify right side
    312.80x = 74,484.12
  5. Step 5: Solve for x
    x = 74,484.12/312.80
  6. Step 6: Final answer
    x = 238.12

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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.