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Finding the Fourth Proportional to 218.79, 328.31 and 88.77

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Solution

The fourth proportional to 218.79, 328.31 and 88.77 is: 133.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    218.79 : 328.31 = 88.77 : x
  2. Step 2: Convert to fraction form
    218.79/328.31 = 88.77/x
  3. Step 3: Cross multiply
    218.79x = 328.31 × 88.77
  4. Step 4: Simplify right side
    218.79x = 29,144.08
  5. Step 5: Solve for x
    x = 29,144.08/218.79
  6. Step 6: Final answer
    x = 133.21

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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.