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Finding the Fourth Proportional to 720.81, 994.72 and 389.24

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Solution

The fourth proportional to 720.81, 994.72 and 389.24 is: 537.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.81 : 994.72 = 389.24 : x
  2. Step 2: Convert to fraction form
    720.81/994.72 = 389.24/x
  3. Step 3: Cross multiply
    720.81x = 994.72 × 389.24
  4. Step 4: Simplify right side
    720.81x = 387,184.58
  5. Step 5: Solve for x
    x = 387,184.58/720.81
  6. Step 6: Final answer
    x = 537.15

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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.