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Finding the Fourth Proportional to 320.78, 442.71 and 247.07

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Solution

The fourth proportional to 320.78, 442.71 and 247.07 is: 340.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.78 : 442.71 = 247.07 : x
  2. Step 2: Convert to fraction form
    320.78/442.71 = 247.07/x
  3. Step 3: Cross multiply
    320.78x = 442.71 × 247.07
  4. Step 4: Simplify right side
    320.78x = 109,378.15
  5. Step 5: Solve for x
    x = 109,378.15/320.78
  6. Step 6: Final answer
    x = 340.98

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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.