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Finding the Fourth Proportional to 485.72, 670.14 and 387.32

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Solution

The fourth proportional to 485.72, 670.14 and 387.32 is: 534.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.72 : 670.14 = 387.32 : x
  2. Step 2: Convert to fraction form
    485.72/670.14 = 387.32/x
  3. Step 3: Cross multiply
    485.72x = 670.14 × 387.32
  4. Step 4: Simplify right side
    485.72x = 259,558.62
  5. Step 5: Solve for x
    x = 259,558.62/485.72
  6. Step 6: Final answer
    x = 534.38

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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.