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Finding the Fourth Proportional to 70.30, 105.40 and 56.77

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Solution

The fourth proportional to 70.30, 105.40 and 56.77 is: 85.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.30 : 105.40 = 56.77 : x
  2. Step 2: Convert to fraction form
    70.30/105.40 = 56.77/x
  3. Step 3: Cross multiply
    70.30x = 105.40 × 56.77
  4. Step 4: Simplify right side
    70.30x = 5,983.56
  5. Step 5: Solve for x
    x = 5,983.56/70.30
  6. Step 6: Final answer
    x = 85.11

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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.