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Finding the Fourth Proportional to 90.32, 135.34 and 72.28

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Solution

The fourth proportional to 90.32, 135.34 and 72.28 is: 108.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.32 : 135.34 = 72.28 : x
  2. Step 2: Convert to fraction form
    90.32/135.34 = 72.28/x
  3. Step 3: Cross multiply
    90.32x = 135.34 × 72.28
  4. Step 4: Simplify right side
    90.32x = 9,782.38
  5. Step 5: Solve for x
    x = 9,782.38/90.32
  6. Step 6: Final answer
    x = 108.31

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.