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Finding the Fourth Proportional to 338.21, 507.30 and 145.70

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Solution

The fourth proportional to 338.21, 507.30 and 145.70 is: 218.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.21 : 507.30 = 145.70 : x
  2. Step 2: Convert to fraction form
    338.21/507.30 = 145.70/x
  3. Step 3: Cross multiply
    338.21x = 507.30 × 145.70
  4. Step 4: Simplify right side
    338.21x = 73,911.07
  5. Step 5: Solve for x
    x = 73,911.07/338.21
  6. Step 6: Final answer
    x = 218.54

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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.