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Finding the Fourth Proportional to 809.53, 1,219.28 and 770.65

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Solution

The fourth proportional to 809.53, 1,219.28 and 770.65 is: 1,160.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.53 : 1,219.28 = 770.65 : x
  2. Step 2: Convert to fraction form
    809.53/1,219.28 = 770.65/x
  3. Step 3: Cross multiply
    809.53x = 1,219.28 × 770.65
  4. Step 4: Simplify right side
    809.53x = 939,631.23
  5. Step 5: Solve for x
    x = 939,631.23/809.53
  6. Step 6: Final answer
    x = 1,160.72

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.