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Finding the Fourth Proportional to 854.03, 1,281.20 and 421.19

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Solution

The fourth proportional to 854.03, 1,281.20 and 421.19 is: 631.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    854.03 : 1,281.20 = 421.19 : x
  2. Step 2: Convert to fraction form
    854.03/1,281.20 = 421.19/x
  3. Step 3: Cross multiply
    854.03x = 1,281.20 × 421.19
  4. Step 4: Simplify right side
    854.03x = 539,628.63
  5. Step 5: Solve for x
    x = 539,628.63/854.03
  6. Step 6: Final answer
    x = 631.86

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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.