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Finding the Fourth Proportional to 90.90, 125.42 and 51.55

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Solution

The fourth proportional to 90.90, 125.42 and 51.55 is: 71.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.90 : 125.42 = 51.55 : x
  2. Step 2: Convert to fraction form
    90.90/125.42 = 51.55/x
  3. Step 3: Cross multiply
    90.90x = 125.42 × 51.55
  4. Step 4: Simplify right side
    90.90x = 6,465.40
  5. Step 5: Solve for x
    x = 6,465.40/90.90
  6. Step 6: Final answer
    x = 71.13

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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.