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Finding the Fourth Proportional to 30.03, 45.12 and 21.03

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Solution

The fourth proportional to 30.03, 45.12 and 21.03 is: 31.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.03 : 45.12 = 21.03 : x
  2. Step 2: Convert to fraction form
    30.03/45.12 = 21.03/x
  3. Step 3: Cross multiply
    30.03x = 45.12 × 21.03
  4. Step 4: Simplify right side
    30.03x = 948.87
  5. Step 5: Solve for x
    x = 948.87/30.03
  6. Step 6: Final answer
    x = 31.60

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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.