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Finding the Fourth Proportional to 105.54, 145.30 and 87.10

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Solution

The fourth proportional to 105.54, 145.30 and 87.10 is: 119.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    105.54 : 145.30 = 87.10 : x
  2. Step 2: Convert to fraction form
    105.54/145.30 = 87.10/x
  3. Step 3: Cross multiply
    105.54x = 145.30 × 87.10
  4. Step 4: Simplify right side
    105.54x = 12,655.63
  5. Step 5: Solve for x
    x = 12,655.63/105.54
  6. Step 6: Final answer
    x = 119.91

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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.