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Finding the Fourth Proportional to 719.20, 1,078.85 and 286.30

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Solution

The fourth proportional to 719.20, 1,078.85 and 286.30 is: 429.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    719.20 : 1,078.85 = 286.30 : x
  2. Step 2: Convert to fraction form
    719.20/1,078.85 = 286.30/x
  3. Step 3: Cross multiply
    719.20x = 1,078.85 × 286.30
  4. Step 4: Simplify right side
    719.20x = 308,873.32
  5. Step 5: Solve for x
    x = 308,873.32/719.20
  6. Step 6: Final answer
    x = 429.47

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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.