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Finding the Fourth Proportional to 145.61, 218.30 and 72.45

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Solution

The fourth proportional to 145.61, 218.30 and 72.45 is: 108.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.61 : 218.30 = 72.45 : x
  2. Step 2: Convert to fraction form
    145.61/218.30 = 72.45/x
  3. Step 3: Cross multiply
    145.61x = 218.30 × 72.45
  4. Step 4: Simplify right side
    145.61x = 15,815.47
  5. Step 5: Solve for x
    x = 15,815.47/145.61
  6. Step 6: Final answer
    x = 108.62

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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.