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Finding the Fourth Proportional to 478.30, 717.86 and 218.69

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Solution

The fourth proportional to 478.30, 717.86 and 218.69 is: 328.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.30 : 717.86 = 218.69 : x
  2. Step 2: Convert to fraction form
    478.30/717.86 = 218.69/x
  3. Step 3: Cross multiply
    478.30x = 717.86 × 218.69
  4. Step 4: Simplify right side
    478.30x = 156,988.80
  5. Step 5: Solve for x
    x = 156,988.80/478.30
  6. Step 6: Final answer
    x = 328.22

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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.