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Finding the Fourth Proportional to 491.12, 678 and 325.72

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Solution

The fourth proportional to 491.12, 678 and 325.72 is: 449.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.12 : 678 = 325.72 : x
  2. Step 2: Convert to fraction form
    491.12/678 = 325.72/x
  3. Step 3: Cross multiply
    491.12x = 678 × 325.72
  4. Step 4: Simplify right side
    491.12x = 220,838.16
  5. Step 5: Solve for x
    x = 220,838.16/491.12
  6. Step 6: Final answer
    x = 449.66

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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.