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Finding the Fourth Proportional to 90.55, 124.20 and 79.62

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Solution

The fourth proportional to 90.55, 124.20 and 79.62 is: 109.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.55 : 124.20 = 79.62 : x
  2. Step 2: Convert to fraction form
    90.55/124.20 = 79.62/x
  3. Step 3: Cross multiply
    90.55x = 124.20 × 79.62
  4. Step 4: Simplify right side
    90.55x = 9,888.34
  5. Step 5: Solve for x
    x = 9,888.34/90.55
  6. Step 6: Final answer
    x = 109.20

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.