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Finding the Fourth Proportional to 145.20, 218.68 and 137.10

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Solution

The fourth proportional to 145.20, 218.68 and 137.10 is: 206.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.20 : 218.68 = 137.10 : x
  2. Step 2: Convert to fraction form
    145.20/218.68 = 137.10/x
  3. Step 3: Cross multiply
    145.20x = 218.68 × 137.10
  4. Step 4: Simplify right side
    145.20x = 29,980.34
  5. Step 5: Solve for x
    x = 29,980.34/145.20
  6. Step 6: Final answer
    x = 206.48

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.