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Finding the Fourth Proportional to 30.19, 45.05 and 28.30

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Solution

The fourth proportional to 30.19, 45.05 and 28.30 is: 42.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.19 : 45.05 = 28.30 : x
  2. Step 2: Convert to fraction form
    30.19/45.05 = 28.30/x
  3. Step 3: Cross multiply
    30.19x = 45.05 × 28.30
  4. Step 4: Simplify right side
    30.19x = 1,274.92
  5. Step 5: Solve for x
    x = 1,274.92/30.19
  6. Step 6: Final answer
    x = 42.23

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.