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Finding the Fourth Proportional to 615.40, 923.55 and 409.90

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Solution

The fourth proportional to 615.40, 923.55 and 409.90 is: 615.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.40 : 923.55 = 409.90 : x
  2. Step 2: Convert to fraction form
    615.40/923.55 = 409.90/x
  3. Step 3: Cross multiply
    615.40x = 923.55 × 409.90
  4. Step 4: Simplify right side
    615.40x = 378,563.15
  5. Step 5: Solve for x
    x = 378,563.15/615.40
  6. Step 6: Final answer
    x = 615.15

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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.