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Finding the Fourth Proportional to 145.82, 218.75 and 128.86

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Solution

The fourth proportional to 145.82, 218.75 and 128.86 is: 193.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.82 : 218.75 = 128.86 : x
  2. Step 2: Convert to fraction form
    145.82/218.75 = 128.86/x
  3. Step 3: Cross multiply
    145.82x = 218.75 × 128.86
  4. Step 4: Simplify right side
    145.82x = 28,186.93
  5. Step 5: Solve for x
    x = 28,186.93/145.82
  6. Step 6: Final answer
    x = 193.30

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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.