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Finding the Fourth Proportional to 770, 1,062.63 and 420.71

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Solution

The fourth proportional to 770, 1,062.63 and 420.71 is: 580.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    770 : 1,062.63 = 420.71 : x
  2. Step 2: Convert to fraction form
    770/1,062.63 = 420.71/x
  3. Step 3: Cross multiply
    770x = 1,062.63 × 420.71
  4. Step 4: Simplify right side
    770x = 447,056.96
  5. Step 5: Solve for x
    x = 447,056.96/770
  6. Step 6: Final answer
    x = 580.59

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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.