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Finding the Fourth Proportional to 90.10, 124.30 and 71.88

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Solution

The fourth proportional to 90.10, 124.30 and 71.88 is: 99.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.10 : 124.30 = 71.88 : x
  2. Step 2: Convert to fraction form
    90.10/124.30 = 71.88/x
  3. Step 3: Cross multiply
    90.10x = 124.30 × 71.88
  4. Step 4: Simplify right side
    90.10x = 8,934.68
  5. Step 5: Solve for x
    x = 8,934.68/90.10
  6. Step 6: Final answer
    x = 99.16

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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.