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Finding the Fourth Proportional to 259.66, 387.85 and 218.66

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Solution

The fourth proportional to 259.66, 387.85 and 218.66 is: 326.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    259.66 : 387.85 = 218.66 : x
  2. Step 2: Convert to fraction form
    259.66/387.85 = 218.66/x
  3. Step 3: Cross multiply
    259.66x = 387.85 × 218.66
  4. Step 4: Simplify right side
    259.66x = 84,804.80
  5. Step 5: Solve for x
    x = 84,804.80/259.66
  6. Step 6: Final answer
    x = 326.60

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.