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Finding the Fourth Proportional to 30.07, 45.03 and 19.90

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Solution

The fourth proportional to 30.07, 45.03 and 19.90 is: 29.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.07 : 45.03 = 19.90 : x
  2. Step 2: Convert to fraction form
    30.07/45.03 = 19.90/x
  3. Step 3: Cross multiply
    30.07x = 45.03 × 19.90
  4. Step 4: Simplify right side
    30.07x = 895.87
  5. Step 5: Solve for x
    x = 895.87/30.07
  6. Step 6: Final answer
    x = 29.80

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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.