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Finding the Fourth Proportional to 457.40, 685.80 and 320.12

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Solution

The fourth proportional to 457.40, 685.80 and 320.12 is: 479.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    457.40 : 685.80 = 320.12 : x
  2. Step 2: Convert to fraction form
    457.40/685.80 = 320.12/x
  3. Step 3: Cross multiply
    457.40x = 685.80 × 320.12
  4. Step 4: Simplify right side
    457.40x = 219,538.30
  5. Step 5: Solve for x
    x = 219,538.30/457.40
  6. Step 6: Final answer
    x = 479.97

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.