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Finding the Fourth Proportional to 145.51, 218.08 and 80.51

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Solution

The fourth proportional to 145.51, 218.08 and 80.51 is: 120.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.51 : 218.08 = 80.51 : x
  2. Step 2: Convert to fraction form
    145.51/218.08 = 80.51/x
  3. Step 3: Cross multiply
    145.51x = 218.08 × 80.51
  4. Step 4: Simplify right side
    145.51x = 17,556.78
  5. Step 5: Solve for x
    x = 17,556.78/145.51
  6. Step 6: Final answer
    x = 120.66

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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.