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Finding the Fourth Proportional to 64.40, 88.39 and 57.34

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Solution

The fourth proportional to 64.40, 88.39 and 57.34 is: 78.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    64.40 : 88.39 = 57.34 : x
  2. Step 2: Convert to fraction form
    64.40/88.39 = 57.34/x
  3. Step 3: Cross multiply
    64.40x = 88.39 × 57.34
  4. Step 4: Simplify right side
    64.40x = 5,067.84
  5. Step 5: Solve for x
    x = 5,067.84/64.40
  6. Step 6: Final answer
    x = 78.70

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.