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Finding the Fourth Proportional to 486.09, 728.71 and 212.11

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Solution

The fourth proportional to 486.09, 728.71 and 212.11 is: 317.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.09 : 728.71 = 212.11 : x
  2. Step 2: Convert to fraction form
    486.09/728.71 = 212.11/x
  3. Step 3: Cross multiply
    486.09x = 728.71 × 212.11
  4. Step 4: Simplify right side
    486.09x = 154,566.68
  5. Step 5: Solve for x
    x = 154,566.68/486.09
  6. Step 6: Final answer
    x = 317.98

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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.