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Finding the Fourth Proportional to 615.70, 923.55 and 380.80

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Solution

The fourth proportional to 615.70, 923.55 and 380.80 is: 571.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.70 : 923.55 = 380.80 : x
  2. Step 2: Convert to fraction form
    615.70/923.55 = 380.80/x
  3. Step 3: Cross multiply
    615.70x = 923.55 × 380.80
  4. Step 4: Simplify right side
    615.70x = 351,687.84
  5. Step 5: Solve for x
    x = 351,687.84/615.70
  6. Step 6: Final answer
    x = 571.20

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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.