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Finding the Fourth Proportional to 615.20, 847.60 and 428.36

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Solution

The fourth proportional to 615.20, 847.60 and 428.36 is: 590.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.20 : 847.60 = 428.36 : x
  2. Step 2: Convert to fraction form
    615.20/847.60 = 428.36/x
  3. Step 3: Cross multiply
    615.20x = 847.60 × 428.36
  4. Step 4: Simplify right side
    615.20x = 363,072.63
  5. Step 5: Solve for x
    x = 363,072.63/615.20
  6. Step 6: Final answer
    x = 590.17

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.