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Finding the Fourth Proportional to 145.15, 200.31 and 79.66

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Solution

The fourth proportional to 145.15, 200.31 and 79.66 is: 109.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.15 : 200.31 = 79.66 : x
  2. Step 2: Convert to fraction form
    145.15/200.31 = 79.66/x
  3. Step 3: Cross multiply
    145.15x = 200.31 × 79.66
  4. Step 4: Simplify right side
    145.15x = 15,955.49
  5. Step 5: Solve for x
    x = 15,955.49/145.15
  6. Step 6: Final answer
    x = 109.92

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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.