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Finding the Fourth Proportional to 486.82, 728.72 and 312.90

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Solution

The fourth proportional to 486.82, 728.72 and 312.90 is: 468.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.82 : 728.72 = 312.90 : x
  2. Step 2: Convert to fraction form
    486.82/728.72 = 312.90/x
  3. Step 3: Cross multiply
    486.82x = 728.72 × 312.90
  4. Step 4: Simplify right side
    486.82x = 228,016.49
  5. Step 5: Solve for x
    x = 228,016.49/486.82
  6. Step 6: Final answer
    x = 468.38

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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.