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Finding the Fourth Proportional to 3.78, 5.20 and 3.16

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Solution

The fourth proportional to 3.78, 5.20 and 3.16 is: 4.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.78 : 5.20 = 3.16 : x
  2. Step 2: Convert to fraction form
    3.78/5.20 = 3.16/x
  3. Step 3: Cross multiply
    3.78x = 5.20 × 3.16
  4. Step 4: Simplify right side
    3.78x = 16.43
  5. Step 5: Solve for x
    x = 16.43/3.78
  6. Step 6: Final answer
    x = 4.35

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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.