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Finding the Fourth Proportional to 485.82, 728.84 and 212.11

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Solution

The fourth proportional to 485.82, 728.84 and 212.11 is: 318.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.82 : 728.84 = 212.11 : x
  2. Step 2: Convert to fraction form
    485.82/728.84 = 212.11/x
  3. Step 3: Cross multiply
    485.82x = 728.84 × 212.11
  4. Step 4: Simplify right side
    485.82x = 154,593.19
  5. Step 5: Solve for x
    x = 154,593.19/485.82
  6. Step 6: Final answer
    x = 318.21

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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.