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Finding the Fourth Proportional to 721.30, 1,082.76 and 288.76

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Solution

The fourth proportional to 721.30, 1,082.76 and 288.76 is: 433.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.30 : 1,082.76 = 288.76 : x
  2. Step 2: Convert to fraction form
    721.30/1,082.76 = 288.76/x
  3. Step 3: Cross multiply
    721.30x = 1,082.76 × 288.76
  4. Step 4: Simplify right side
    721.30x = 312,657.78
  5. Step 5: Solve for x
    x = 312,657.78/721.30
  6. Step 6: Final answer
    x = 433.46

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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.