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Finding the Fourth Proportional to 85.07, 127.65 and 56.21

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Solution

The fourth proportional to 85.07, 127.65 and 56.21 is: 84.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.07 : 127.65 = 56.21 : x
  2. Step 2: Convert to fraction form
    85.07/127.65 = 56.21/x
  3. Step 3: Cross multiply
    85.07x = 127.65 × 56.21
  4. Step 4: Simplify right side
    85.07x = 7,175.21
  5. Step 5: Solve for x
    x = 7,175.21/85.07
  6. Step 6: Final answer
    x = 84.34

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.