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Finding the Fourth Proportional to 770.39, 1,063.11 and 421.07

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Solution

The fourth proportional to 770.39, 1,063.11 and 421.07 is: 581.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.39 : 1,063.11 = 421.07 : x
  2. Step 2: Convert to fraction form
    770.39/1,063.11 = 421.07/x
  3. Step 3: Cross multiply
    770.39x = 1,063.11 × 421.07
  4. Step 4: Simplify right side
    770.39x = 447,643.73
  5. Step 5: Solve for x
    x = 447,643.73/770.39
  6. Step 6: Final answer
    x = 581.06

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Half scale
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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.