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Finding the Fourth Proportional to 45.30, 67.80 and 31.74

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Solution

The fourth proportional to 45.30, 67.80 and 31.74 is: 47.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    45.30 : 67.80 = 31.74 : x
  2. Step 2: Convert to fraction form
    45.30/67.80 = 31.74/x
  3. Step 3: Cross multiply
    45.30x = 67.80 × 31.74
  4. Step 4: Simplify right side
    45.30x = 2,151.97
  5. Step 5: Solve for x
    x = 2,151.97/45.30
  6. Step 6: Final answer
    x = 47.50

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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.