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Finding the Fourth Proportional to 28, 38.80 and 27.55

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Solution

The fourth proportional to 28, 38.80 and 27.55 is: 38.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    28 : 38.80 = 27.55 : x
  2. Step 2: Convert to fraction form
    28/38.80 = 27.55/x
  3. Step 3: Cross multiply
    28x = 38.80 × 27.55
  4. Step 4: Simplify right side
    28x = 1,068.94
  5. Step 5: Solve for x
    x = 1,068.94/28
  6. Step 6: Final answer
    x = 38.18

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.