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Finding the Fourth Proportional to 64.45, 87.76 and 64.25

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Solution

The fourth proportional to 64.45, 87.76 and 64.25 is: 87.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    64.45 : 87.76 = 64.25 : x
  2. Step 2: Convert to fraction form
    64.45/87.76 = 64.25/x
  3. Step 3: Cross multiply
    64.45x = 87.76 × 64.25
  4. Step 4: Simplify right side
    64.45x = 5,638.58
  5. Step 5: Solve for x
    x = 5,638.58/64.45
  6. Step 6: Final answer
    x = 87.49

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.