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Finding the Fourth Proportional to 77.00, 106.21 and 47.50

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Solution

The fourth proportional to 77.00, 106.21 and 47.50 is: 65.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.00 : 106.21 = 47.50 : x
  2. Step 2: Convert to fraction form
    77.00/106.21 = 47.50/x
  3. Step 3: Cross multiply
    77.00x = 106.21 × 47.50
  4. Step 4: Simplify right side
    77.00x = 5,045.10
  5. Step 5: Solve for x
    x = 5,045.10/77.00
  6. Step 6: Final answer
    x = 65.53

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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.