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Finding the Fourth Proportional to 720.09, 993.69 and 405.32

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Solution

The fourth proportional to 720.09, 993.69 and 405.32 is: 559.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.09 : 993.69 = 405.32 : x
  2. Step 2: Convert to fraction form
    720.09/993.69 = 405.32/x
  3. Step 3: Cross multiply
    720.09x = 993.69 × 405.32
  4. Step 4: Simplify right side
    720.09x = 402,757.46
  5. Step 5: Solve for x
    x = 402,757.46/720.09
  6. Step 6: Final answer
    x = 559.32

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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.