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Finding the Fourth Proportional to 55.55, 83.30 and 21.31

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Solution

The fourth proportional to 55.55, 83.30 and 21.31 is: 31.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.55 : 83.30 = 21.31 : x
  2. Step 2: Convert to fraction form
    55.55/83.30 = 21.31/x
  3. Step 3: Cross multiply
    55.55x = 83.30 × 21.31
  4. Step 4: Simplify right side
    55.55x = 1,775.12
  5. Step 5: Solve for x
    x = 1,775.12/55.55
  6. Step 6: Final answer
    x = 31.96

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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.