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Finding the Fourth Proportional to 770.62, 1,063.41 and 421.31

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Solution

The fourth proportional to 770.62, 1,063.41 and 421.31 is: 581.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.62 : 1,063.41 = 421.31 : x
  2. Step 2: Convert to fraction form
    770.62/1,063.41 = 421.31/x
  3. Step 3: Cross multiply
    770.62x = 1,063.41 × 421.31
  4. Step 4: Simplify right side
    770.62x = 448,023.16
  5. Step 5: Solve for x
    x = 448,023.16/770.62
  6. Step 6: Final answer
    x = 581.38

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Double scale
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1.5x scale

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.