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Finding the Fourth Proportional to 770.59, 1,063.41 and 421.28

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Solution

The fourth proportional to 770.59, 1,063.41 and 421.28 is: 581.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.59 : 1,063.41 = 421.28 : x
  2. Step 2: Convert to fraction form
    770.59/1,063.41 = 421.28/x
  3. Step 3: Cross multiply
    770.59x = 1,063.41 × 421.28
  4. Step 4: Simplify right side
    770.59x = 447,993.36
  5. Step 5: Solve for x
    x = 447,993.36/770.59
  6. Step 6: Final answer
    x = 581.36

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.