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Finding the Fourth Proportional to 90.26, 124.62 and 71.80

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Solution

The fourth proportional to 90.26, 124.62 and 71.80 is: 99.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.26 : 124.62 = 71.80 : x
  2. Step 2: Convert to fraction form
    90.26/124.62 = 71.80/x
  3. Step 3: Cross multiply
    90.26x = 124.62 × 71.80
  4. Step 4: Simplify right side
    90.26x = 8,947.09
  5. Step 5: Solve for x
    x = 8,947.09/90.26
  6. Step 6: Final answer
    x = 99.13

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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.