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Finding the Fourth Proportional to 658.89, 988.31 and 220.11

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Solution

The fourth proportional to 658.89, 988.31 and 220.11 is: 330.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.89 : 988.31 = 220.11 : x
  2. Step 2: Convert to fraction form
    658.89/988.31 = 220.11/x
  3. Step 3: Cross multiply
    658.89x = 988.31 × 220.11
  4. Step 4: Simplify right side
    658.89x = 217,535.81
  5. Step 5: Solve for x
    x = 217,535.81/658.89
  6. Step 6: Final answer
    x = 330.15

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1.5x scale

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.