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Finding the Fourth Proportional to 864.80, 1,298.40 and 540.80

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Solution

The fourth proportional to 864.80, 1,298.40 and 540.80 is: 811.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    864.80 : 1,298.40 = 540.80 : x
  2. Step 2: Convert to fraction form
    864.80/1,298.40 = 540.80/x
  3. Step 3: Cross multiply
    864.80x = 1,298.40 × 540.80
  4. Step 4: Simplify right side
    864.80x = 702,174.72
  5. Step 5: Solve for x
    x = 702,174.72/864.80
  6. Step 6: Final answer
    x = 811.95

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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.