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Finding the Fourth Proportional to 82.51, 123.75 and 28.40

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Solution

The fourth proportional to 82.51, 123.75 and 28.40 is: 42.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.51 : 123.75 = 28.40 : x
  2. Step 2: Convert to fraction form
    82.51/123.75 = 28.40/x
  3. Step 3: Cross multiply
    82.51x = 123.75 × 28.40
  4. Step 4: Simplify right side
    82.51x = 3,514.50
  5. Step 5: Solve for x
    x = 3,514.50/82.51
  6. Step 6: Final answer
    x = 42.59

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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.