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Finding the Fourth Proportional to 218.78, 328.10 and 64.66

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Solution

The fourth proportional to 218.78, 328.10 and 64.66 is: 96.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    218.78 : 328.10 = 64.66 : x
  2. Step 2: Convert to fraction form
    218.78/328.10 = 64.66/x
  3. Step 3: Cross multiply
    218.78x = 328.10 × 64.66
  4. Step 4: Simplify right side
    218.78x = 21,214.95
  5. Step 5: Solve for x
    x = 21,214.95/218.78
  6. Step 6: Final answer
    x = 96.97

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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.