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Finding the Fourth Proportional to 145.80, 201.22 and 86.78

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Solution

The fourth proportional to 145.80, 201.22 and 86.78 is: 119.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.80 : 201.22 = 86.78 : x
  2. Step 2: Convert to fraction form
    145.80/201.22 = 86.78/x
  3. Step 3: Cross multiply
    145.80x = 201.22 × 86.78
  4. Step 4: Simplify right side
    145.80x = 17,462.16
  5. Step 5: Solve for x
    x = 17,462.16/145.80
  6. Step 6: Final answer
    x = 119.77

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.