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Finding the Fourth Proportional to 768.81, 1,061 and 419.50

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Solution

The fourth proportional to 768.81, 1,061 and 419.50 is: 578.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    768.81 : 1,061 = 419.50 : x
  2. Step 2: Convert to fraction form
    768.81/1,061 = 419.50/x
  3. Step 3: Cross multiply
    768.81x = 1,061 × 419.50
  4. Step 4: Simplify right side
    768.81x = 445,089.50
  5. Step 5: Solve for x
    x = 445,089.50/768.81
  6. Step 6: Final answer
    x = 578.93

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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.