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Finding the Fourth Proportional to 812.95, 1,218.88 and 380.23

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Solution

The fourth proportional to 812.95, 1,218.88 and 380.23 is: 570.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.95 : 1,218.88 = 380.23 : x
  2. Step 2: Convert to fraction form
    812.95/1,218.88 = 380.23/x
  3. Step 3: Cross multiply
    812.95x = 1,218.88 × 380.23
  4. Step 4: Simplify right side
    812.95x = 463,454.74
  5. Step 5: Solve for x
    x = 463,454.74/812.95
  6. Step 6: Final answer
    x = 570.09

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.