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Finding the Fourth Proportional to 720.52, 994.31 and 405.77

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Solution

The fourth proportional to 720.52, 994.31 and 405.77 is: 559.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.52 : 994.31 = 405.77 : x
  2. Step 2: Convert to fraction form
    720.52/994.31 = 405.77/x
  3. Step 3: Cross multiply
    720.52x = 994.31 × 405.77
  4. Step 4: Simplify right side
    720.52x = 403,461.63
  5. Step 5: Solve for x
    x = 403,461.63/720.52
  6. Step 6: Final answer
    x = 559.96

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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.