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Finding the Fourth Proportional to 40, 55.42 and 39.28

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Solution

The fourth proportional to 40, 55.42 and 39.28 is: 54.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    40 : 55.42 = 39.28 : x
  2. Step 2: Convert to fraction form
    40/55.42 = 39.28/x
  3. Step 3: Cross multiply
    40x = 55.42 × 39.28
  4. Step 4: Simplify right side
    40x = 2,176.90
  5. Step 5: Solve for x
    x = 2,176.90/40
  6. Step 6: Final answer
    x = 54.42

Related Problems

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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.