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Finding the Fourth Proportional to 658.30, 987.23 and 219.45

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Solution

The fourth proportional to 658.30, 987.23 and 219.45 is: 329.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.30 : 987.23 = 219.45 : x
  2. Step 2: Convert to fraction form
    658.30/987.23 = 219.45/x
  3. Step 3: Cross multiply
    658.30x = 987.23 × 219.45
  4. Step 4: Simplify right side
    658.30x = 216,646.53
  5. Step 5: Solve for x
    x = 216,646.53/658.30
  6. Step 6: Final answer
    x = 329.10

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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.