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Finding the Fourth Proportional to 320, 442.40 and 306.40

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Solution

The fourth proportional to 320, 442.40 and 306.40 is: 423.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    320 : 442.40 = 306.40 : x
  2. Step 2: Convert to fraction form
    320/442.40 = 306.40/x
  3. Step 3: Cross multiply
    320x = 442.40 × 306.40
  4. Step 4: Simplify right side
    320x = 135,551.36
  5. Step 5: Solve for x
    x = 135,551.36/320
  6. Step 6: Final answer
    x = 423.60

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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.