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Finding the Fourth Proportional to 518.32, 715.31 and 285.45

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Solution

The fourth proportional to 518.32, 715.31 and 285.45 is: 393.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.32 : 715.31 = 285.45 : x
  2. Step 2: Convert to fraction form
    518.32/715.31 = 285.45/x
  3. Step 3: Cross multiply
    518.32x = 715.31 × 285.45
  4. Step 4: Simplify right side
    518.32x = 204,185.24
  5. Step 5: Solve for x
    x = 204,185.24/518.32
  6. Step 6: Final answer
    x = 393.94

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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.