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Finding the Fourth Proportional to 145.90, 218.85 and 140.30

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Solution

The fourth proportional to 145.90, 218.85 and 140.30 is: 210.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.90 : 218.85 = 140.30 : x
  2. Step 2: Convert to fraction form
    145.90/218.85 = 140.30/x
  3. Step 3: Cross multiply
    145.90x = 218.85 × 140.30
  4. Step 4: Simplify right side
    145.90x = 30,704.66
  5. Step 5: Solve for x
    x = 30,704.66/145.90
  6. Step 6: Final answer
    x = 210.45

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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.