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Finding the Fourth Proportional to 43.10, 64.28 and 38.78

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Solution

The fourth proportional to 43.10, 64.28 and 38.78 is: 57.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    43.10 : 64.28 = 38.78 : x
  2. Step 2: Convert to fraction form
    43.10/64.28 = 38.78/x
  3. Step 3: Cross multiply
    43.10x = 64.28 × 38.78
  4. Step 4: Simplify right side
    43.10x = 2,492.78
  5. Step 5: Solve for x
    x = 2,492.78/43.10
  6. Step 6: Final answer
    x = 57.84

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.