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Finding the Fourth Proportional to 91.24, 125.85 and 71.80

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Solution

The fourth proportional to 91.24, 125.85 and 71.80 is: 99.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    91.24 : 125.85 = 71.80 : x
  2. Step 2: Convert to fraction form
    91.24/125.85 = 71.80/x
  3. Step 3: Cross multiply
    91.24x = 125.85 × 71.80
  4. Step 4: Simplify right side
    91.24x = 9,036.03
  5. Step 5: Solve for x
    x = 9,036.03/91.24
  6. Step 6: Final answer
    x = 99.04

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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.