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Finding the Fourth Proportional to 485, 725.66 and 380.50

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Solution

The fourth proportional to 485, 725.66 and 380.50 is: 569.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    485 : 725.66 = 380.50 : x
  2. Step 2: Convert to fraction form
    485/725.66 = 380.50/x
  3. Step 3: Cross multiply
    485x = 725.66 × 380.50
  4. Step 4: Simplify right side
    485x = 276,113.63
  5. Step 5: Solve for x
    x = 276,113.63/485
  6. Step 6: Final answer
    x = 569.31

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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.