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Finding the Fourth Proportional to 615.90, 849.60 and 419.70

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Solution

The fourth proportional to 615.90, 849.60 and 419.70 is: 578.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.90 : 849.60 = 419.70 : x
  2. Step 2: Convert to fraction form
    615.90/849.60 = 419.70/x
  3. Step 3: Cross multiply
    615.90x = 849.60 × 419.70
  4. Step 4: Simplify right side
    615.90x = 356,577.12
  5. Step 5: Solve for x
    x = 356,577.12/615.90
  6. Step 6: Final answer
    x = 578.95

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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.