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Finding the Fourth Proportional to 71.28, 98.36 and 40.19

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Solution

The fourth proportional to 71.28, 98.36 and 40.19 is: 55.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.28 : 98.36 = 40.19 : x
  2. Step 2: Convert to fraction form
    71.28/98.36 = 40.19/x
  3. Step 3: Cross multiply
    71.28x = 98.36 × 40.19
  4. Step 4: Simplify right side
    71.28x = 3,953.43
  5. Step 5: Solve for x
    x = 3,953.43/71.28
  6. Step 6: Final answer
    x = 55.46

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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.