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Finding the Fourth Proportional to 47.12, 70.86 and 42.89

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Solution

The fourth proportional to 47.12, 70.86 and 42.89 is: 64.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    47.12 : 70.86 = 42.89 : x
  2. Step 2: Convert to fraction form
    47.12/70.86 = 42.89/x
  3. Step 3: Cross multiply
    47.12x = 70.86 × 42.89
  4. Step 4: Simplify right side
    47.12x = 3,039.19
  5. Step 5: Solve for x
    x = 3,039.19/47.12
  6. Step 6: Final answer
    x = 64.50

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.