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Finding the Fourth Proportional to 858.82, 1,287.21 and 447.34

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Solution

The fourth proportional to 858.82, 1,287.21 and 447.34 is: 670.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    858.82 : 1,287.21 = 447.34 : x
  2. Step 2: Convert to fraction form
    858.82/1,287.21 = 447.34/x
  3. Step 3: Cross multiply
    858.82x = 1,287.21 × 447.34
  4. Step 4: Simplify right side
    858.82x = 575,820.52
  5. Step 5: Solve for x
    x = 575,820.52/858.82
  6. Step 6: Final answer
    x = 670.48

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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.