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Finding the Fourth Proportional to 1,078.29, 1,616.94 and 420.30

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Solution

The fourth proportional to 1,078.29, 1,616.94 and 420.30 is: 630.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,078.29 : 1,616.94 = 420.30 : x
  2. Step 2: Convert to fraction form
    1,078.29/1,616.94 = 420.30/x
  3. Step 3: Cross multiply
    1,078.29x = 1,616.94 × 420.30
  4. Step 4: Simplify right side
    1,078.29x = 679,599.88
  5. Step 5: Solve for x
    x = 679,599.88/1,078.29
  6. Step 6: Final answer
    x = 630.26

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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.