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Finding the Fourth Proportional to 65.30, 90.08 and 54.30

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Solution

The fourth proportional to 65.30, 90.08 and 54.30 is: 74.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.30 : 90.08 = 54.30 : x
  2. Step 2: Convert to fraction form
    65.30/90.08 = 54.30/x
  3. Step 3: Cross multiply
    65.30x = 90.08 × 54.30
  4. Step 4: Simplify right side
    65.30x = 4,891.34
  5. Step 5: Solve for x
    x = 4,891.34/65.30
  6. Step 6: Final answer
    x = 74.91

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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.