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Finding the Fourth Proportional to 60.30, 90.45 and 19.72

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Solution

The fourth proportional to 60.30, 90.45 and 19.72 is: 29.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    60.30 : 90.45 = 19.72 : x
  2. Step 2: Convert to fraction form
    60.30/90.45 = 19.72/x
  3. Step 3: Cross multiply
    60.30x = 90.45 × 19.72
  4. Step 4: Simplify right side
    60.30x = 1,783.79
  5. Step 5: Solve for x
    x = 1,783.79/60.30
  6. Step 6: Final answer
    x = 29.58

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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.