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Finding the Fourth Proportional to 131.40, 181.30 and 79.64

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Solution

The fourth proportional to 131.40, 181.30 and 79.64 is: 109.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    131.40 : 181.30 = 79.64 : x
  2. Step 2: Convert to fraction form
    131.40/181.30 = 79.64/x
  3. Step 3: Cross multiply
    131.40x = 181.30 × 79.64
  4. Step 4: Simplify right side
    131.40x = 14,438.73
  5. Step 5: Solve for x
    x = 14,438.73/131.40
  6. Step 6: Final answer
    x = 109.88

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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.